Brake System - on Board Diagnostic (OBD) - ABS & ESP Audi A6 C5

On Board Diagnostic (OBD) for ABS and ESP, general notes

This Manual is intended as a practical aid for technicians and electricians in the workshop when working on the Audi A6 and dealing with malfunctions and problems reported by the customer.

If the malfunction is related to one of the systems with On Board Diagnostic (OBD) capability covered here, this Manual should give you the information you need to solve the problem.

We (that is the authors who prepare service literature at the factory) have exactly the same aim as the personnel in the workshops: to make sure that customers are satisfied and to restore their confidence in the product.

The production of a Repair Manual involves a lot of work. Our intention is to describe and explain the technical features and repair measures in such a way that repairs can be completed quickly and correctly. This is not always easy, and good results are only possible if you read the Manual carefully.

Here are some basic points to start with

1. The control module of a system with On Board Diagnostic (OBD) function detects faults and malfunctions during vehicle operation and stores them in a permanent memory, the contents of which remain intact if the power supply from the battery is interrupted.
2. The On Board Diagnostic (OBD) function relates to the electrical and electronic parts of a system; in other words it only registers malfunctions which have an effect on the electrical signals.
3. The On Board Diagnostic (OBD) function enables malfunctions to be traced quickly and efficiently using VAG 1551 scan tool, or the VAG 1552 vehicle testing system, in operating mode 1 "Rapid data transfer". To do this, the control module of the system concerned must be able to communicate with the scan tool via the diagnostic link-up.
4. The diagnostic connector is the interface for communication between the control module and the scan tool.
5. To start the troubleshooting procedure, connect the scan tool to the diagnostic connector and establish the communication link with the control module of the system concerned. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
6. When the communication link has been established, you can then select the required troubleshooting functions provided by the on-board system you are testing. These functions are programmed in the form of fixed diagnostic routines, which are described in the relevant sections of this Manual. After first checking the control module version, start with function 02 "Check DTC Memory". See «SCAN TOOL FUNCTIONS, SELECTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__scan-tool-functions-selecting) .
7. Any DTC's which may be stored in the memory will be indicated on the display of the scan tool. The information displayed can then be used in conjunction with a DTC table, which enables you to trace the cause of the malfunction and perform the necessary repair quickly and efficiently.
8. The On Board Diagnostic (OBD) function distinguishes between static and sporadic malfunctions. If a malfunction which has been stored in the memory as a static malfunction is no longer present when the ignition is switched on, it is converted into a sporadic malfunction.
9. Sporadic malfunctions are identified as such by "/SP" appearing in the display on VAG 1551 scan tool.
10. A sporadic malfunction is erased automatically if it no longer occurs over a certain number of driving cycles.
11. Static malfunctions remain stored in the DTC memory until the memory is erased with VAG 1551 scan tool.
12. If the control module has to be replaced, first read out the control module version. This appears in the display of the scan tool together with the coding when communication is established between the control module and the scan tool. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

VAG 1551 scan tool, connecting and entering address word

Note. The VAG 1552 scan tool or VAS 5051 vehicle diagnostic, testing and information system can be used instead of the VAG 1551 scan tool, however VAG 1552 scan tool does not have the facility for printing out the information in the display.

1. Observe test requirements for the system concerned.

1. With ignition switched off, connect scan tool to the diagnostic connector using VAG 1551/3B cable. The diagnostic connector is under the dashboard on the left side.

Scheme 1

Indicated on display

Scheme 2

Note. If the display remains blank, check connections of diagnostic connector The PRINT button is used for switching on the printer (the indicator lamp in the button comes on when the printer is switched on). Depending on the program, additional operating information can be printed out by pressing HELP button of VAG 1551 scan tool.

Scheme 3

1. Switch on ignition.
2. Switch on printer by pressing PRINT button of scan tool.
3. Press button -1- for "Rapid data transfer" operating mode.

Indicated on display

Scheme 4

Note. The address word selects the control module of the on-board system that you wish to test with the scan tool. It is made up of two digits, which are given in the relevant sections of this Manual.

For instance, press buttons -0- and -3- to enter the address word for "Brake electronics".

Indicated on display

Scheme 5

1. Press -Q- button to confirm input.

Indicated on display after entering address word 03

Scheme 6

Note. If an error occurs in the diagnostic communication between the scan tool and the control module, the display will show one of the four following messages

Scheme 7

Scheme 8

1. Press HELP button to obtain a print-out of the possible causes of the error.
2. Test diagnostic wiring ("K" wire).
3. Test power supply and Ground (GND) connection to ABS control module (w/EDL) -J104-.

Indicated on display

Scheme 9

1. Repair error.
2. After repairing possible causes of error, enter address word 03 for brake electronics once again and confirm with -Q- button.

If the diagnostic communication between the scan tool and the control module is established and works properly, the display will now show the control module identification (X), the system designation (Y), the hardware and software version (Z), the coding (V) and the workshop code (W).

Scheme 10

Note. The --> button is used for moving forward within the program. The various on-board systems to be tested are described in more detail in the relevant sections. The control module index can only be changed by installing a new control module. If the control module identification number does not appear in the display, check diagnostic wiring.

1. Press --> button.

Indicated on display

Scheme 11

Scan tool functions, selecting

After establishing diagnostic communication, checking the control module version and pressing --> button, proceed as follows

Indicated on display

Scheme 12

1. (Function selection, for example, 02 - Check DTC Memory)

You can now select one of the functions listed below. Start the troubleshooting routine with function 02 "Check DTC Memory".

1. Check Control Module Versions
2. Check DTC Memory
3. Output Diagnostic Test Mode
4. Basic Setting
5. Erase DTC memory
6. End Output
7. Code Control Module
8. Read Measuring Value Block
9. Read Individual Measuring Value
10. Adaptation
11. Login procedure

The functions "Erase DTC memory" and "End Output" are described below.

The other functions listed here are described in the relevant sections.

When a function has been performed and completed, Press --> button in order to return to the start position of the troubleshooting routine: "Select function".

Requirements

1. DTC memory has been checked.

1. Press --> button.

Indicated on display

Scheme 13

1. Press buttons -0- and -5- for the function "Erase DTC memory".

Indicated on display

Scheme 14

1. Press -Q- button to confirm input.

Indicated on display

Scheme 15

1. Press --> button.

Indicated on display

Scheme 16

Scheme 17

1. If DTC Memory Not Interrogated appears in the display, the test sequence has not been performed correctly.
2. Keep exactly to the test sequence: First check DTC memory, then erase DTC memory in the same diagnostic cycle.

Ending output

Indicated on display

Scheme 18

1. Press buttons -0- and -6- for the function "End Output".

Indicated on display

Scheme 19

Scheme 20

1. Press -Q- button to confirm input. Indicated on display Switch off ignition. Disconnect scan tool.

Troubleshooting ABS and ESP, safety precautions and general notes

1. The ABS/EDL/ASR and ESP are safety systems; knowledge of the systems is essential for performing repair work.

Road testing

1. Certain malfunctions will only be detected when the car is moving, so the system can be checked by performing a road test. Maintain a speed above 60 km/h for a period of 30 seconds. After ensuring that it is safe to do so, apply brakes hard enough to activate ABS-controlled braking (this can be felt from the pulsation at the brake pedal).

If there is a complaint on the vehicle, perform the troubleshooting procedure as follows

Troubleshooting procedure

1. First switch on the ignition and observe the warning lights. The table in the chapter on "Warning light functions" will allow you to make an initial statement.
2. Observe the requirements for test detailed under «REQUIREMENTS FOR TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__requirements-for-test) .
3. Connect the VAG 1551 scan tool and select "Brake electronics" with address word 03. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
4. Check the control module version
5. Check DTC memory. If a code is stored, make a note of it and erase DTC memory. See «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
6. End data transfer via the "End Output" function. See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
7. Repair malfunction according to DTC table. Select "Brake electronics" once again using address word 03. Check and erase DTC memory.
8. Conclude the transfer of data with the function "End Output". Disconnect VAG 1551 scan tool.
9. Make sure that all plug connectors are properly connected. Perform a road test. See «TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__troubleshooting-abs-and-esp-safety-precautions) . The warning lights should not come on during the road test. If they do, repeat the troubleshooting steps described above.

Note. If the connector is not plugged into the control module when the vehicle is moving, this may result in a spurious (non-existent) malfunction being registered in the DTC memory of another control module. The operation of the brake system is impaired because the brake pressure at the rear wheels is no longer controlled by the electronic brake force distribution function. This can result in excessive braking at the rear, and the tail of the vehicle may break loose unexpectedly. This could cause an accident if the vehicle is driven in this condition.

1. Switch off the ignition before removing and installing components. Disconnect the battery Ground (GND) strap (on vehicles with coded radio, first obtain the security coding).

1. If a component is indicated as malfunctioning, only replace it if you are sure that the electrical wiring for that component is in proper condition. The wiring must be able to transmit the necessary signals without interference or resistance. Check the wiring for

1. Corrosion and loose contacts (intermittent open circuit) in the plug connectors and Ground (GND) connections. If any of the plug contacts are bent, broken or corroded, use the VAS 1978 wiring repair kit to install new contacts
2. Open circuits
3. Short circuits to Ground (GND) or to positive (live voltage)

Note. The instructions supplied with VAS 1978 wiring repair kit normally do not permit repairs to the wiring of the ABS/EDL and the associated systems. However, this only applies to the screened wiring in the systems.

1. When replacing the control module, be sure not to install an incorrect control module. Check control module version first. It appears on the display of VAG 1551 scan tool after the diagnostic link is established between VAG 1551 scan tool and the control module, or can be called up using function 01 "Check Control Module Versions". The vehicle features can also be identified by a combination of letters on the vehicle data sticker, which is located in the spare wheel well.

1AC: Anti-lock brake system (ABS)

1AH: Anti-lock brake system (ABS) with electronic differential lock (EDL)

1AJ: Anti-lock brake system (ABS) with electronic differential lock (EDL) and traction control system (ASR)

1AT: Anti-lock brake system (ABS) with electronic differential lock (EDL), traction control system (ASR) and electronic stabilization program (ESP)

1. Absolute cleanliness is required when working on the hydraulic unit. Carefully clean the hydraulic connections and adjacent parts. Do not use aggressive cleaning agents such as brake cleaner, gasoline, thinners or any products which contain mineral oil, such as oils or grease etc. Do not disconnect hydraulic lines until you have cleaned the connections.
2. Observe the appropriate precautions regarding the handling of brake fluid.
3. Place removed parts on a clean surface and cover them over. Do not use fluffy cloths or rags.
4. Only use genuine packaged parts, and only remove replacement parts from their packaging immediately prior to installation.
5. Bleed the brake system if connections in the system have to be opened. See «BLEEDING BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
6. Welding work with electric welding equipment can affect the ABS/EDL or ABS/EDL/ASR system.

Requirements for test

1. The vehicle must be equipped with the approved wheels and tire sizes, which must be the same on all four wheels. Check inflation pressures all round.
2. Brake system mechanical and hydraulic parts must be in order: No leaks in hydraulic lines or connections (visual inspection of hydraulic unit, brake calipers, wheel cylinders, tandem master brake cylinder).
3. Wheel bearings and wheel bearing play OK.
4. Wheel speed sensors must be installed correctly.
5. Supply voltage must be OK (not less than 10.0 V).
6. Connector on ABS control module (w/EDL) -J104- must be properly attached, with retainer catch engaged.
7. The diagnostic procedure can only be started with the vehicle stationary and the ignition switched on (or with engine running). The diagnosis cannot be started if wheel speed exceeds 2.75 km/h, and will be terminated if the speed exceeds 20 km/h.
8. When testing the ABS/EDL and ASR systems, ensure that the vehicle's electronics are not subjected to electromagnetic interference: keep the vehicle away from equipment with a high current draw, such as electric welding units.

Technical information required

1. Applicable wiring diagram.
2. Component locations of electrical components See «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) . Brakes, brake mechanics See «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
3. Brakes, brake hydraulics See «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
4. Notes on repairing common malfunctions on current models.

Bus

A bus is a defined path or "highway" for the transmission and distribution of data signals.

CAN

A Controller Area Network is a bus system working with two wires, known as bus wires. The bus wires transmit data signals in serial form (one after the other) to the control modules connected into the system.

The signals are transmitted via CAN-Bus. Further details and test instructions can be found under CAN-BUS, TESTING . The CAN-Bus employs only two bus wires, which are capable of transmitting all the required data. Two wires are employed in order to be able to detect faults in the wires themselves.

CAN-Bus for ESP

The ESP function relies on an exchange of signals between ABS control module (w/EDL) -J104- (-item 2- in the illustration), the engine control module (-item 3-) the transmission control module (-item 4-) and the steering angle sensor -G85- (-item 1-).

Scheme 21

The matching resistors at the ends of the CAN-Bus are rated at 120 ohm, and are located in the ABS control module (w/EDL) -J104- (-item 2-) and in the engine control module (-item 3-).

As of implementation of control modules 8D0 907 389 D/E, the CAN-Bus is terminated centrally in the ECM with a resistance of approx. 66 ohms. All other control modules in the CAN connection, e.g. -J104-, are terminated with a high-resistance of 2.6 k Ohms.

The DTC table may instruct you to test the bus

1. By referring to the appropriate wiring diagram, check how many control modules are connected to the data bus.
2. Check that the multi-pin connectors on the control modules are properly seated.
3. Connect VAG 1551 scan tool or VAG 1552 scan tool and press button -0- twice to select the function "Automatic test sequence"
4. Before testing the bus wires, make sure that there are no malfunctions in any of the control modules which are connected to the bus.

Note. A malfunctionregistered in one of the control modules does not affect the data bus system directly, but can result from a malfunction of some kind in one of the systems. This may be a faulty sensor, for example. The result is that the sensor signal can no longer be processed for transmission via the data bus. A malfunction of this kind has an indirect effect on the data bus system, and will upset the communication with other control modules which require the signal from the affected sensor.

If a malfunction exists

1. Repair this malfunction first
2. Make a note of any codes and erase the DTC memories of all control modules. See «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. Press buttons -0- and -6- for the function "End Output" and confirm entry with the -Q- button.
4. End the output on the scan tool with the function "End Output". See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
5. Repair the malfunctions as described in the DTC table. When all malfunctions have been repaired
6. If communication between the control modules is still not working properly, test the bus wires.

When tracing malfunctions in the bus wires, distinguish between two possible cases

1. Two control modules communicating via a CAN-Bus
2. Three or more control modules communicating via a CAN-Bus

Scheme 22

Scheme 23

1. Switch off ignition.
2. Disconnect both control modules.
3. Check for open circuit in one of the bus wires
4. Check for short circuit between the two bus wires
5. Check for short to positive or short to Ground (GND) in one of the bus wires. If no malfunction can be found in the bus wires
6. As a trial measure, replace whichever control module is easier (or less expensive) to change.
7. If communication between the control modules via the bus is still not working properly, replace the second control module.

Three or more control modules communicating via a CAN-Bus

1. Read out the DTC's stored in the control modules.

Example 1

From the codes present in the DTC memories, you can see that control module -1- has no connection to control modules -2- or -3-.

Scheme 24

Scheme 25

1. Switch off ignition.
2. Disconnect the control modules which are linked by the bus wires and check whether there is an open circuit in one of the bus wires.
3. If no malfunction can be found in the bus wires replace control module 1.

Example 2

From the codes present in the DTC memories, you can see that control module -2- has no connection to control modules -1- or -3-.

Scheme 26

Scheme 27

1. Switch off ignition.
2. Disconnect the control modules which are linked by the bus wires and check whether there is an open circuit in one of the bus wires
3. If no malfunction can be found in the bus wires replace control module 2.

Example 3

From the codes registered by the DTC memories, you can see that none of the control modules are able to transmit or receive signals.

Scheme 28

Scheme 29

Scheme 30

1. Switch off ignition.
2. Disconnect the control modules which are linked by the bus wires and check for a short circuit between the bus wires
3. Check the bus wires for short to positive and short to Ground (GND).
4. If the cause of the malfunction "Faulty hardware" cannot be found in bus wires, check whether one of the control modules is responsible for causing the malfunction. At this stage all the control modules which communicate via the CAN-Bus are disconnected.
5. Connect one of the control modules.
6. Connect VAG 1551 scan tool or VAG 1552 scan tool. Switch on ignition and erase the DTC memory of control module which has just been connected. End Output from scan tool with function 06 "End Output".
7. Switch ignition off and then on again.
8. Leave the ignition switched on for 10 seconds. Then check DTC memory of the control module that has just been connected, using the scan tool.
9. If the malfunction "Faulty hardware" is now indicated, replace control module which has just been connected.
10. If the malfunction "Faulty hardware" is not indicated, connect next control module, and repeat above procedure.

Bosch 5.3 ABS/EDL system, function

The Bosch 5.3 system has a more compact design. The ABS return flow pump -V39-, the ABS hydraulic unit -N55- and the ABS control module (w/EDL) -J104- are combined to form the hydraulic control module. The bolts which secure the individual components of the hydraulic control module must not be unscrewed.

The direct connection between these components reduces possible sources of malfunctions. There is no provision for repairing the hydraulic control module - it must be replaced if necessary.

The brake system is split diagonally into two hydraulic circuits: one supplying the left front and right rear brakes and one supplying the right front and left rear brakes.

The individual components of the Bosch 5.3 system have the following functions

Electronic brake force distribution

The ABS control module (w/EDL) -J104- is programmed with specially designed software for "electronic brake force distribution", which takes over the function of brake pressure limiter.

In the event of failure of the ABS, the signal which activates the ABS/EDL warning light and the brake system warning symbol is sent to the instrument cluster via the wire from contact 21 of ABS control module (w/EDL) -J104-. In vehicles built up to week 20/1997, the instrument cluster simply registers whether or not this signal is present: The brake system warning symbol normally comes on in addition to the ABS/EDL warning light.

In vehicles built from week 21/1997 onward, the brake system warning symbol no longer comes on at all times when a failure of the ABS has occurred.

In cases where a failure of the ABS has occurred, but the electronic brake force distribution function can still be maintained by a back-up feature, the signal sent to the instrument cluster is pulsed. The instrument cluster distinguishes between three conditions: no signal present, pulsed signal, and continuous signal present. The ABS/EDL warning light and the brake system warning symbol come on in accordance with the signal received.

Scheme 31

1. Terminal 15
2. Signal for activation of ABS/EDL warning light and brake system warning symbol
3. Supply voltage for ABS/EDL warning light
4. Supply voltage for brake system warning symbol

1. During phase "A" (after ignition is switched on) the ABS/EDL warning light is activated for two seconds during the self-test by means of signal "2", and comes on. During this phase an internal function in the instrument cluster suppresses the activation of the brake system warning symbol.
2. During phase "B", signal "2" is not present. The ABS/EDL warning light and brake system warning symbol do not come on.
3. In phase "C", On Board Diagnostic (OBD) has detected a malfunction which does not cause the electronic brake force distribution function to be switched off. Signal "2" is pulsed. Only the ABS/EDL warning light comes on.
4. In phase "D", On Board Diagnostic (OBD) has detected a malfunction which causes the electronic brake force distribution function to be switched off. Signal "2" is present continuously. Both the ABS/EDL warning light and brake system warning symbol come on.

If the brake system warning symbol comes on, this indicates that the electronic brake force distribution function has failed. In this condition the vehicle should only be driven with extra caution. See TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES , Road testing.

For further information on the activation of the warning lights in connection with the electronic brake force distribution function, see WARNING LIGHT FUNCTIONS OVERVIEW , table of warning light functions. Refer to the notes in the table under CHECK CONTROL MODULE VERSIONS for identification of what type of electronic brake force distribution function is installed in the vehicle.

The anti-lock brake system (ABS) prevents the wheels from locking when brakes are applied by the driver.

EDL

The electronic differential lock (EDL) is an aid when driving away from a standstill. An electronically controlled brake application on the spinning driven wheel provides a torque reaction point for the differential. This enables the wheel with better traction to transmit engine power onto the road. The EDL is effective in both forward and reverse directions.

EDL is standard equipment on vehicles with all wheel drive, where it acts on all four wheels (on vehicles with front wheel drive it acts only on the front wheels). A mechanical differential lock is not required.

The EDL active control function can be initiated at road speeds up to 40 km/h. Once the EDL has become active, it cuts out automatically at a predetermined upper speed threshold, which is 40 km/h on vehicles with front wheel drive and 80 km/h on vehicles with all wheel drive.

Suction dampers are installed in the hydraulic unit to assist the build-up of pressure in the corresponding wheel brake cylinders when the EDL is active. The operating range of the pressure limiting valve in the hydraulic unit is 170 +/- 25 bar.

To prevent the brakes from overheating, the EDL control function is suppressed if the temperature of the brakes exceeds a certain value which is defined in the ABS control module (w/EDL) -J104-. The temperature of the brakes is calculated by the control module by means of a simulation formula. The EDL is then reactivated when the calculated temperature drops below a predetermined lower threshold. The operation of the conventional brake system and the ABS function are not affected by this automatic cut-off feature.

When the ignition is switched off, the calculated temperature of the hot brakes is stored in memory until the ignition is switched on again. When the ignition is switched on, the instrument cluster sends a time signal which enables the ABS control module (w/EDL) -J104- to calculate the period the vehicle has been left standing. This period is put into the temperature simulation formula to calculate the new temperature of the brakes. If the vehicle has been left standing for more than one hour, the control module will automatically assume a brake temperature equal to the lowest value in the simulation formula.

If the EDL is switched off because the temperature limit has been exceeded, this will be indicated in the measured value block for a period of 20 ignition cycles. See READ MEASURING VALUE BLOCK (FUNCTION 08) .

ASR

ASR (traction control system) is only installed on vehicles with front wheel drive. On these vehicles it is important to check the control module coding. See CODE CONTROL MODULE (FUNCTION 07) . The traction control function relies on an exchange of signals between ABS control module (w/EDL) -J104-, the engine control module and the transmission control module, in other words a communication link between the control modules.

There are two types of communication link in use

1. Signals transmitted via a number of separate wires.
2. Signals transmitted via «CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . The CAN-Bus consists of only two wires, which transmit all the necessary signals.

You can establish which of these communication systems is employed by using the function "Check Control Module Versions". See CHECK CONTROL MODULE VERSIONS (FUNCTION 01) . And by referring to the table of control module versions. See ABS, EDL, ASR CONTROL MODULE VERSIONS .

The ASR traction control system prevents the driven wheels from spinning under acceleration: the system operates by reducing engine torque and is active at all speeds. The EDL and ASR functions act together to assist acceleration.

Depending on the engine version, the ASR also incorporates an overrun torque limiting function (MSR). MSR prevents the driven wheels from locking up due to excessive engine braking torque, for instance when the driver changes down from 3rd to 2nd gear. The engine braking effect is reduced via the idle volume control.

If required, the ASR function can be switched off and then on again by means of the ASR push-button switch in the center console. The MSR overrun torque limiting function is not affected by the ASR switch. The ASR will be activated again automatically the next time the ignition is switched on. When the system is deactivated, the ASR warning light comes on in the instrument cluster. See READ MEASURING VALUE BLOCK (FUNCTION 08) . The warning light flashes at a rate of three times per second when the control function starts working.

Warning light functions overview

1. If the On Board Diagnostic (OBD) detects a malfunction in the system, it will be displayed by the warning lights when the ignition is switched on. Warning lights are located in the instrument cluster.

Instrument cluster without driver information display

1. The illustration shows ABS warning light -K47- (right -arrow-), warning light for brake system -K118- (center -arrow-, red symbol "brake system malfunction(" and the traction control indicator light -K86- (left -arrow-).

Scheme 32

Instrument cluster with driver information display

1. Warning light for brake system -K118- is not installed on instrument clusters with driver information display. The red symbol "brake system malfunction" appears on the display.
2. If the brake system is not fully functional, but the ABS warning light -K47- and the brake system warning symbol do not come on, this means the malfunction must be sought in the conventional braking system (mechanical/hydraulic components). See «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .

Scheme 33

Scheme 34

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 35

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
2. For check control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
3. To check DTC memory, see «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) .

Scheme 36

1. For check control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
2. To check DTC memory, see «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) .

Scheme 37

1. To check DTC memory, see «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) .

Scheme 38

1. For check control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
2. To check DTC memory, see «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) .

Scheme 39

1. To check DTC memory, see «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
3. For measuring value blocks, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .

Scheme 40

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

On Board Diagnostic (OBD) function

The On Board Diagnostic (OBD) function of the ABS/EDL system can detect a total of 14 different malfunctions (23 in the case of vehicles with ASR traction control).

Note. The system performs a self-test routine every time the ignition is switched on. This process is indicated by the yellow ABS warning light -K47- coming on. On vehicles with ASR the traction control indicator light -K86- will also come on. The warning lights will go out after about 2 seconds. The self-test routine continues for a short time when the vehicle is moving, as some malfunctions can only be detected above a certain speed. During the self-test process there will be some audible noise from the relays and the return flow pump in the hydraulic control module, and a slight pulsation at the brake pedal. This is unavoidable, and is not a malfunction which requires repair. If a malfunction is detected by the On Board Diagnostic (OBD) function, the system concerned is switched off automatically for the duration of the current driving cycle. This is indicated by the relevant warning light in the instrument cluster. For further details refer to the section on WARNING LIGHT FUNCTIONS . See WARNING LIGHT FUNCTIONS OVERVIEW . The above does not apply to either of the two malfunctions "00526 Brake light switch" and "01203 ABS/Dash pan. ins. electr. connection" in DIAGNOSTIC TROUBLE CODE (DTC) TABLE . If one of these malfunctions is detected, none of the warning lights will come on. These malfunctions only affect the operation of the EDL.

Technical data of On Board Diagnostic (OBD)

1. DTC memory Permanent memory: contents remain intact when power supply is interrupted.
2. Data output Rapid data transfer (operating mode 1) The ABS warning light -K47-,the brake system warning symbol and the traction control indicator light -K86- (on vehicles with traction control) will come on in the instrument cluster if a malfunction has been detected and the ABS/EDL and ASR systems are switched off.
3. Functions 01- Check Control Module Versions. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) . 02- Check DTC Memory. See «ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__abs-edl-and-abs-edl-asr) . 03- Output Diagnostic Test Mode. See «OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__output-diagnostic-test-mode-function-03) . 05- Erase DTC memory. See «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 06- End Output. See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) . 07- Code Control Module. See «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__code-control-module-function-07) . 08- Read Measuring Value Block. See «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .

Check Control Module Versions (function 01)

1. Connect VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. Go to start position of program by pressing --> button

Indicated on display

Scheme 41

1. Press buttons -0- and -1- for the function "Check Control Module Versions" and confirm entry with -Q- button.

Note. The control module version can only be altered by installing a new control module. Also refer to the parts catalog for the correct ABS control module (w/EDL) -J104- for the vehicle.

Indicated on display

Scheme 42

The coding is only shown on vehicles with traction control system (ASR); coding control module. See CODE CONTROL MODULE (FUNCTION 07) .

The workshop code, WSC XXXXX, identifies the workshop which performed the last coding of the control module.

1) Control module index

2) System designation

3) Hardware and software status

1. Press --> button.

Indicated on display

Scheme 43

Scheme 44

Scheme 45

Scheme 46

Scheme 47

Code Control Module (function 07)

If a control module with traction control function (ASR) is replaced, or if one of the following codes are stored in the DTC memory of the control module, the control module must be coded according to the type of engine and transmission.

1. "ABS/EDL/transmission - electrical connection"
2. "Control module incorrectly coded"
3. "CAN-Bus - message missing from transmission control module"

Note. The coding can only be performed if a workshop code is stored in VAG 1551 scan tool. The 5-digit coding will appear when the control module identification is displayed.

1. Connect VAG 1551 scan tool and select address word 03: "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) and Press --> button.
3. Press --> button.

Indicated on display

Scheme 48

1. Press buttons -0- and -7- for the function "Code Control Module".

Indicated on display

Scheme 49

1. Press -Q- button to confirm input.

Indicated on display

Scheme 50

1. Enter the required code and confirm with -Q- button.

Scheme 51

Scheme 52

The display will show the control module identification and the coding that has been entered (For example, 00000).

Scheme 53

1. Press --> button.

Indicated on display

Scheme 54

1. Press buttons -0- and -6- for the function "End Output" and confirm entry with the -Q- button.

Read Measuring Value Block (function 08)

The control module can supply test data (measured values). These measured values can provide information about the operational condition of the system and the sensors connected to it. In many cases the data supplied can be used to help trace and repair malfunctions. The test data provided by the Bosch 5.3 ABS/EDL are grouped in four Display Groups, which can be called up via Display Group numbers.

1. Observe the relevant safety precautions when road testing the vehicle. See «TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__troubleshooting-abs-and-esp-safety-precautions) .
2. Connect VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Note. When the printer is switched on, the contents of the display will be printed out on the scan tool log. When reading measured value block, also check wiring and connectors for intermittent loose contacts.

1. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) and press --> button.

Indicated on display

Scheme 55

1. Press buttons -0- and -8- for the function "Read Measuring Value Block".

Indicated on display

Scheme 56

1. Press -Q- button to confirm input.

Indicated on display

Scheme 57

1. Press buttons -0-, -0- and -1-.
2. Press -Q- button to confirm input.

Read measuring value block: display group 1

Note. Display zones 1 to 4 show the actual wheel speeds (at the tire circumference) in km/h. These are calculated by ABS control module (w/EDL) -J104- on the basis of the signals received from the wheel speed sensors. If one of the display zones shows no reading, proceed as for DTC's 00283, 00285, 00287, 00290 "Speed sensor". See DIAGNOSTIC TROUBLE CODE (DTC) TABLE . In order to check that the speed sensor signals are correctly assigned to the four wheels, the vehicle must be raised. On vehicles with manual transmission put the gear shift in neutral. On vehicles with automatic transmission move the selector lever to position "N". Turn the relevant wheel by hand, and at the same time prevent the other driven wheels from rotating. When the vehicle is accelerated uniformly on a dry surface, the displayed values will increase continuously in rising whole numbers (for example, to 6km/h, 7km/h, 8 km/h...). The difference between displayed values 1 to 4 should be not be more than +/-1 km/h(error from out-of-round-wheels). If the values jump (for instance from 6km/h, 7km/h, to 12 km/h) or if the difference between the displayed values is greater than +/-1 km/h, then check the installation of the wheel speed sensors and rotors.

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- (VAG 1551 scan tool) or buttons uparrow and down arrow (VAG 1552 scan tool).

Scheme 58

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 59

1. Press buttons -0-, -0- and -2-.
2. Press -Q- button to confirm input.

Scheme 60

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool).

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 61

Note. For Display Group 3

1. If you wish to read out the display zones for engine speed and actual engine torque with the engine running, you must first interrupt the diagnostic link between the scan tool and the control module using the function "End Output". See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) . Then start the engine and set up the diagnostic link between scan tool and control module once again.

1. Press buttons -0- and -8- for the function "Read Measuring Value Block".
2. Press -Q- button to confirm input.
3. Press buttons -0-, -0- and -3-.
4. Press -Q- button to confirm input.

Scheme 62

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
2. For DTC table, see «DIAGNOSTIC TROUBLE CODE (DTC) TABLE»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool).

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 63

1. Press buttons -0-, -0- and -4-.
2. Press -Q- button to confirm input.

Scheme 64

Output Diagnostic Test Mode (function 03)

The Output Diagnostic Test Mode enables you to check the function of the final control elements, which are the actuators energized by the control module after processing the incoming signals from the sensors.

The function of the final control elements includes all functions and properties of the final control elements under operating conditions, for example

1. An electrically operated hydraulic valve which opens and closes when activated by the control module.
2. The relay of an electric motor which starts the motor when activated by the control module.

Before running an Output Diagnostic Test Mode it is advisable to ensure that there are no electrical malfunctions in the system you wish to test. This will enable you to recognize any mechanical malfunctions. Perform the troubleshooting procedure as described in TROUBLESHOOTING PROCEDURE before starting the Output Diagnostic Test Mode.

When you have made sure that there are no electrical malfunctions in the system, you will be able to identify any mechanical malfunctions in the individual control elements (actuators) if the results of the diagnosis are not as specified on the following pages. In this case, replace the affected component.

With the Bosch 5.3 ABS/EDL system the Output Diagnostic Test Mode enables you to check the electrically actuated hydraulic valves and the pump motor in the hydraulic control module. You can also check that the brake lines going to the four wheels are connected correctly.

Note. The vehicle must be raised until all wheels are free to turn. A second technician is required to check whether the wheels are locked or can be turned. The -C- button can be used to exit from the test sequence at any time. If you then wish to perform the Output Diagnostic Test Mode again, you must first interrupt the diagnosis link using the function End Output. See ENDING OUTPUT , and then start the sequence once again. To avoid overloading the final control elements they are only actuated during the test sequence for a period of 60 (or 90) seconds. The final control test will be terminated if --> button is not pressed within this period. The ABS/EDL warning light and the brake system warning symbol flash during the Output Diagnostic Test Mode. If the brake pedal is pressed repeatedly this will exhaust the vacuum in the brake servo. For this reason, the brake pedal must be pressed harder in order to achieve the same braking effect. It may be advisable to start the engine briefly to build up vacuum in the servo.

When you perform the function Output Diagnostic Test Mode the individual test steps are shown in the second line of the display on VAG 1551 scan tool. The following abbreviations are used

I = Inlet valve

O = Outlet valve

FL = Front Left

FR = Front Right

RL = Rear Left

RR = Rear Right

VBAT = Battery voltage at valve

0V = 0 Volt; No voltage at valve

Locked/free = Wheel condition; must be checked by 2nd technician

Hydr-P = Hydraulic pump

1. Connect VAG 1551 scan tool and select address word 03: Brake electronics. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) and Press --> button.

Indicated on display

Scheme 65

1. Press buttons -0- and -3- for the function "Output Diagnostic Test Mode".

Indicated on display

Scheme 66

1. Press -Q- button to confirm input.

Indicated on display

ABS return flow pump -V39- should start running audibly.

Scheme 67

When you put your foot on the brake pedal you can feel it vibrating. This is because the hydraulic pump is producing pressure pulses in the brake lines, which induce vibrations that can be felt at the pedal.

The pressure pulses in the brake lines are not sufficient to lock the wheels.

Scheme 68

(Scheme 69) is a schematic diagram of the hydraulic circuit of an ABS/EDL system. This will give a better understanding of the various test steps in the Output Diagnostic Test Mode.

1. The grey-shaded components are active.
2. Thin solid lines represent hydraulic lines or hoses which are not under pressure.
3. Thick broken lines represent hydraulic lines or hoses working as suction lines.
4. Thick solid lines represent hydraulic lines or hoses which are under pressure.

1. Press --> button.

Indicated on display

Scheme 69

1. Press --> button.

Scheme 70

Indicated on display

When you press brake pedal, brake fluid pressure will be built up in all four wheel brake cylinders. All four wheels will be locked. (Scheme 72)

Scheme 71

This presupposes that the mechanical and hydraulic components of the brake system are working properly, which means that the master cylinder is able to build up pressure in all four wheel brake cylinders and there are no leaks in the hydraulic lines, hoses and connections. If the wheels do not lock, perform a visual inspection of the brake fluid reservoir, the master cylinder, the hydraulic unit and the wheel cylinders.

To start with, concentrate on the left front wheel. The function of the control elements for this wheel is tested first.

Note. This test step in the Output Diagnostic Test Mode corresponds to the pressure build-up phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 72

Keep pressing the brake pedal.

Scheme 73

In (Scheme 74), the inlet valve is activated, which interrupts the brake line. However, the fluid pressure is still maintained in the wheel cylinder. The left front wheel remains locked.

Note. This test step in the Output Diagnostic Test Mode corresponds to the maintain pressure phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 74

Keep pressing the brake pedal.

The inlet valve and outlet valve for the left front wheel are activated. The hydraulic pump starts running and reduces fluid pressure in the wheel cylinder via the open outlet valve. (Scheme 76)

Scheme 75

The brake pedal must not give, and should press back harder against your foot.

You should now be able to turn left front wheel.

If you cannot turn the wheel, check whether the brake line for the left front wheel is correctly connected. If this is the case, this indicates that there is a mechanical malfunction in one of the valves, providing that there is no electrical malfunction in the system. Replace the hydraulic control module.

If the brake pedal gives under your foot, this means that the inlet valve or the non-return valve connected in parallel with the inlet valve is leaking. Replace the hydraulic control module.

Note. This test step in the Output Diagnostic Test Mode corresponds to the pressure reduction phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 76

The ABS return flow pump -V39- should stop running.

Keep pressing brake pedal. Only the inlet valve is now activated, and this interrupts the brake line. If the inlet valve is not leaking you should be able to turn the front left wheel. (Scheme 78)

Scheme 77

If you cannot turn the wheel, this means that the inlet valve or the non-return valve connected in parallel with the inlet valve is leaking. Replace the hydraulic control module.

1. Press --> button.

Indicated on display

Scheme 78

Keep pressing brake pedal. The inlet valve is no longer activated and does not interrupt the brake line. (Scheme 80) The brake pedal will give perceptibly under your foot. Fluid pressure will be built up again in the left front wheel cylinder. The wheel will be locked.

Scheme 79

1. Press --> button.

Indicated on display

Scheme 80

1. Press --> button.

Continue the Output Diagnostic Test Mode in order to check the right front, left rear and right rear wheels in turn. The test steps are the same as for the left front wheel, so they are not described in detail.

Indicated on display

Scheme 81

1. Press --> button.

Indicated on display

Scheme 82

1. Press --> button.

Indicated on display

Scheme 83

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 84

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 85

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 86

1. Press --> button.

Indicated on display

Scheme 87

1. Press --> button.

Indicated on display

Scheme 88

1. Press --> button.

Indicated on display

Scheme 89

1. Press --> button.

Indicated on display

Scheme 90

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 91

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 92

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 93

1. Press --> button.

Indicated on display

Scheme 94

1. Press --> button.

Indicated on display

Scheme 95

1. Press --> button.

Indicated on display

Scheme 96

1. Press --> button.

Indicated on display

Scheme 97

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 98

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 99

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 100

1. Press --> button.

Indicated on display

Scheme 101

1. Press --> button.

Scheme 102

Indicated on display (Scheme 103) Only required for troubleshooting on vehicles with EDL built from week 21/1997 onward. On these vehicles, this test step was revised together with the introduction of the back-up feature for electronic brake force distribution. On vehicles built before week 21/1997 the hydraulic pump is not activated. This test step can be disregarded on vehicles not equipped with EDL.

Refer to notes in the table under " CHECK CONTROL MODULE VERSIONS for identification of what type of electronic brake force distribution function is installed in the vehicle.

Scheme 103

The EDL change-over valve (left) and the EDL inlet valve are activated. (Scheme 104) ABS return flow pump -V39- runs for one second. The pump draws brake fluid out of the fluid reservoir via the EDL inlet valve, and builds up pressure in the EDL-controlled wheel cylinders. These wheels will then be locked.

If this is not the case, this indicates that there is a mechanical malfunction in one of the valves, provided that there are no electrical malfunctions in the system. Replace the hydraulic control module.

This test step cannot be performed on vehicles not equipped with EDL. These vehicles do not have the EDL valves and the pressure limiting valve.

1. Press --> button.

Indicated on display

Scheme 104

Note. The Output Diagnostic Test Mode is completed. The ABS/EDL warning light and the brake system warning light go out.

1. Press --> button.

Indicated on display

Scheme 105

Note. If the ABS/EDL warning light does not go out, this indicates a malfunction in the system. Keep exactly to the specified test sequence. See TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES .

1. Press buttons -0- and -6- for the function "End Output" and confirm entry with the -Q- button.

Electrical testing

1. If the On Board Diagnostic (OBD) does not give any indication of the source of the malfunction, work through the complete Electrical testing.
2. If the On Board Diagnostic (OBD) provides a direct indication of the source of the malfunction, only carry out the test steps recommended in the DTC table (specific testing).

1. An Automatic test sequence must first be performed to establish that any malfunctions present in the transmission and engine control modules can only originate from the ABS/EDL.

1. Connect VAG 1551 scan tool and select address word 00 with ignition switched on. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. After completing the Electrical testing, check and erase the DTC memories of the transmission and engine control modules.

Scheme 106

1. The multi-pin connector between the wiring harness and ABS control module (w/EDL) -J104- must be in proper condition, without bent, broken or corroded contacts. Replace any damaged contacts using VAS 1978 wiring repair kit.

Note. The instructions supplied with VAS 1978 wiring repair kit normally do not permit repairs to the wiring of the ABS and its associated systems. However, this only applies to the screened wiring in the systems.

1. Switch ignition and electrical consumers off before commencing the check (headlights, lighting, fan, etc.).

Test equipment required

1. VAG 1598 test box
2. VAG 1598/27 adapter
3. VAG 1594 auxiliary test set
4. VAG 1526 tester hand-held multimeter

Connecting VAG 1598 test box with VAG 1598/27 adapter

1. Switch off ignition.
2. Connect VAG 1598/27 adapter to VAG 1598 test box. Pull multi-pin connector off ABS control module (w/EDL) -J104-, and connect VAG 1598/27 adapter and VAG 1598 test box to connector on ABS/EDL wiring harness.

The socket designations on VAG 1598 test box are identical with the contact designations on ABS control module (w/EDL) -J104- and on the wiring harness connector

Scheme 107

Contact assignment of multi-pin connector on wiring harness for ABS control module (w/EDL) -J104-.

Note. All contacts not listed are currently not assigned and must not be connected to other components.

Scheme 108

Scheme 109

Scheme 110

Note. Regarding test table: The socket designations of the VAG 1598 test box are identical to the contact designations of the ABS control module (w/EDL) -J104- in the wiring diagram. Incorrect test procedures can cause damage to the system: do not make connections between any contacts other than those listed in the table The specified values refer to the readings obtained on VAG 1526 tester and are not necessarily applicable for other test units. If the readings obtained do not match the specifications, carry out malfunction repair measures in the right-hand part of the table. If the specified values are achieved, also check wiring for intermittent loose contacts and short circuit to positive and Ground (GND). This applies especially to sporadic malfunctions. Use only VAG 1594 auxiliary test set for checking continuity (bridging leads). If the measured figures only differ slightly from the specifications, clean the sockets and plugs of the testers and adapter leads (with contact spray G 000 700 04) and repeat the check. Before replacing components, check the wiring and connections again, particularly if the specification calls for a resistance reading of less than 10 ohms.

Scheme 111

Scheme 112

Scheme 113

1. To adjust brake light switch, see «BRAKELIGHT SWITCH»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system__brakelight-switch) .

Scheme 114

Scheme 115

Scheme 116

Scheme 117

Scheme 118

Scheme 119

Scheme 120

Scheme 121

Scheme 122

ABS, EDL and ABS, EDL, ASR Diagnostic Trouble Code (DTC) memory, checking

1. Observe «REQUIREMENTS FOR TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__requirements-for-test) .
2. Connect VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
3. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) . Press --> button.
4. Press buttons -0- and -2- to select function "Check DTC Memory" and confirm with button -Q-.

Note. Every malfunction that can be detected by the system has a 5-digit DTC, which is listed in the left-hand column of the DTC table. The message identifying the malfunction and the DTC will be printed out on the printer of VAG 1551 scan tool if the PRINT button is pressed. The malfunction does not appear on the display of VAG 1551 scan tool. The contents of the DTC memory remains stored until the memory is erased. See ERASING DTC MEMORY . Sporadically occurring malfunctions are additionally identified as such, with "/SP" appearing on the right of the display. See ON BOARD DIAGNOSTIC (OBD) FOR ABS AND ESP, GENERAL NOTES . Static malfunctions which cannot be detected when the vehicle is stationary are also identified with "/SP" after the ignition has been switched off and then on again. The following table includes all the malfunctions which can be detected by the ABS control module (w/EDL) -J104- and displayed and printed out by VAG 1551 scan tool. Malfunctions are listed according to DTC's.

Scheme 123

1. For warning light functions, see «WARNING LIGHT FUNCTIONS OVERVIEW»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__warning-light-functions-overview) .
2. For output diagnostic test mode, see «OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__output-diagnostic-test-mode-function-03) .
3. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 124

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
2. To replace front wheel bearing, see «SUSPENSION - FRONT»(/audi/a6/c5-1997-2001/remont/suspension-front/#suspension-front) .
3. For output diagnostic test mode, see «OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__output-diagnostic-test-mode-function-03) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
5. For road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 125

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
2. To replace front wheel bearing, see «SUSPENSION - FRONT»(/audi/a6/c5-1997-2001/remont/suspension-front/#suspension-front) .
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
5. For control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
6. For road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 126

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
2. To replace rear wheel bearing, see SUSPENSION - REAR article.
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
5. For control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
6. For road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 127

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .
2. To replace rear wheel bearing, see SUSPENSION - REAR article.
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .
5. For control module version, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
6. For road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 128

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .

Scheme 129

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-function-08) .

Scheme 130

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 131

Scheme 132

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 133

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 134

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To check coding of control module, see «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__code-control-module-function-07) .

Scheme 135

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 136

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 137

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 138

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. For control module coding, see «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__code-control-module-function-07) .

Scheme 139

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 140

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__electrical-testing) .

Scheme 141

Scheme 142

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To check control module versions, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .
4. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 143

Scheme 144

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To code ABS control module, see «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__code-control-module-function-07) .
4. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 145

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 146

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 147

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 148

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To check control module versions, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) .

Scheme 149

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 150

1. For Bosch 5.3 function, see «BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__bosch-53-absedl-system-function) .
2. For table of control module versions, see «ABS, EDL, ASR CONTROL MODULE VERSIONS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 151

Electronic Stabilization Program (ESP) Bosch 5.3

The Electronic Stabilization Program (ESP) is designed to stabilize the dynamic handling response of the vehicle by counteracting any tendency toward oversteer or understeer.

ESP is an expanded version of the existing on-board safety systems ABS/EDL and ABS/EDL/ASR.

ESP enhances the degree of control in critical dynamic conditions, i.e. when the driver approaches the handling limits of the vehicle. Compared with the existing safety systems, ESP further reduces the risk of skidding and improves handling.

However, ESP is not able to overcome the physical limits of the available road adhesion.

ESP, function

ESP incorporates the functions of electronic brake force distribution, ABS, EDL and ASR. The individual elements of the system are as follows

If required, the ASR and ESP control functions can be switched off and then on again by means of the ASR/ESP push-button switch in the center console. This switch is overridden when the driver presses the brake pedal: ESP will remain active at all times during braking. Both functions, ASR and ESP, will be reactivated automatically the next time the ignition is switched on.

The condition of the ASR/ESP switch can be verified using the function 08 "Read Measuring Value Block". See READ MEASURING VALUE BLOCK (FUNCTION 08) , Display Group 2.

When the system is deactivated, the ASR/ESP warning light comes on in the instrument cluster. The warning light flashes at rate of three times per second when the control function starts working.

The brake system is split diagonally into two hydraulic circuits: one supplying the left front and right rear brakes and one supplying the right front and left rear brakes.

The ABS control module (w/EDL) -J104- is programmed with specially designed software for electronic brake force distribution, which takes over the function of the mechanical or hydraulic brake pressure limiter.

In cases where a failure of the ABS has occurred, but the electronic brake force distribution function can still be maintained by a back-up feature, the signal sent to the instrument cluster is pulsed. The instrument cluster distinguishes between three conditions: no signal present, pulsed signal, and continuous signal present. The ABS/EDL warning light and the brake system warning symbol come on in accordance with the signal received.

Scheme 152

1. Terminal 15
2. Signal for activation of ABS/EDL warning light and brake system warning symbol
3. Supply voltage for ABS/EDL warning light
4. Supply voltage for brake system warning symbol

Scheme 153

1. During phase "A" (after ignition is switched on) the ABS/EDL warning light is activated for two seconds during the self-test by means of signal "2", and comes on. During this phase an internal function in the instrument cluster suppresses the activation of the brake system warning symbol.
2. During phase "B", signal "2" is not present. The ABS/EDL warning light and brake system warning symbol do not come on.
3. In phase "C", On Board Diagnostic (OBD) has detected a malfunction which does not cause the electronic brake force distribution function to be switched off. Signal "2" is pulsed. Only the ABS/EDL warning light comes on.
4. In phase "D", On Board Diagnostic (OBD) has detected a malfunction which causes the electronic brake force distribution function to be switched off. Signal "2" is present continuously. Both the ABS/EDL warning light and brake system warning symbol come on.

If the brake system warning symbol comes on, this indicates that the electronic brake force distribution function is out of action. If the vehicle has to be driven in this condition, extra caution is required. See TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES , Road testing.

For further information on the activation of the warning lights in connection with the electronic brake force distribution function. See WARNING LIGHT FUNCTIONS TABLE .

The anti-lock brake system (ABS) prevents the wheels from locking when the brakes are applied by the driver. It controls the brake pressure applied to the individual wheel brake cylinders according to the rate of acceleration and retardation at the wheels (which depend on the amount of wheel slip) in such a way that the wheels can develop maximum road adhesion and thus the best possible braking effect.

The electronic differential lock (EDL) is an aid when driving away from a standstill. An electronically controlled brake application on the spinning driven wheel provides a torque reaction point for the differential. This enables the wheel with better traction to make use of the engine power. The EDL is effective in both forward and reverse directions.

On vehicles with all wheel drive, EDL acts on all four wheels; a mechanical differential lock is not required.

In conjunction with ESP, the EDL is active at all speeds.

The traction control function (ASR) requires an exchange of signals between ABS control module (w/EDL) -J104-, the engine control module and the transmission control module (automatics only), in other words a communication link between the control modules.

These signals are transmitted via CAN-BUS .

The ASR traction control system prevents the driven wheels from spinning under acceleration: the system operates by reducing engine torque and is active at all speeds. The EDL and ASR functions act together to assist acceleration.

The electronic stabilization program (ESP) is designed to stabilize the dynamic handling response of the vehicle by counteracting any tendency toward oversteer or understeer. The familiar functions of electronic brake force distribution, ABS, EDL and ASR (traction control) are incorporated in the system, but the characteristic function of the ESP is a controlled brake application at individual wheels.

Examples

In an oversteer condition the tail of the vehicle breaks out, and the vehicle rotates further about its vertical axis (rotational movement) than is required to maintain course through the corner. The system counteracts this excessive movement by applying a controlled braking force at the outside front wheel.

Scheme 154

In an understeer condition the front end of the vehicle does not follow the required cornering radius, and breaks away toward the outside of the corner. The vehicle does not rotate far enough about its vertical axis to maintain course through the corner. The system increases the amount of rotation by applying a controlled braking force at the inside rear wheel.

Scheme 155

With the exception of the new components described below, the locations of the system components are the same as with the Bosch 5.3 system. The procedures for removing and installing components are described in

See ANTILOCK BRAKE SYSTEM .

Hydraulic pump for traction control -V156- (ESP) and sender 1 for brake booster -G201

The hydraulic pump for traction control -V156- (ESP) and sender 1 for brake booster -G201- are on the left side of the engine compartment (seen in the .

Scheme 156

The ABS hydraulic unit -N55- with ABS return flow pump -V39- are assisted by the hydraulic pump for traction control -V156- (ESP). This enables the system to build up the required brake fluid pressure rapidly in the wheel brake cylinders.

Do not loosen the bolts securing the individual components of the ABS hydraulic unit -N55- and the hydraulic pump for traction control -V156- (ESP). The hydraulic pump for traction control -V156- (ESP) and the sender 1 for brake booster -G201- form a single unit and must always be replaced together if necessary.

The sender 1 for brake booster -G201- measures the fluid pressure generated in the brake system.

Steering angle sensor -G85

Steering angle sensor -G85- is located in a combined housing with airbag spiral spring/return spring with slip ring -F138-.

The airbag spiral spring/return spring with slip ring -F138- is installed over the central shaft of the steering column, and clipped onto the steering column switch.

Scheme 157

There are two versions of airbag spiral spring/return spring with slip ring -F138

One with and one without the wiring required for steering wheels with additional functions. The illustration shows the version for steering wheels with additional functions.

The method for removing and installing the steering angle sensor -G85- is the same as for the airbag coil connector.

The steering angle sensor -G85- does not have its own DTC memory, and is therefore monitored by the diagnostic function of ABS control module (w/EDL) -J104- via CAN-Bus.

The steering angle sensor -G85- is wired directly to the power supply from terminal 30. This power supply is used by the sender for a period of one hour after the ignition is switched off; during this time there will be a current draw of up to 100 mA. At the end of this period the current draw will drop below 0.5 mA, and the sender is no longer active. The sender is re-activated via terminal 15 when the ignition is switched on again.

The sender requires this power supply from terminal 30 after the ignition is switched off to enable it to recognize any movement of the steering wheel with the ignition off.

If the ignition has been switched off for more than one hour, the sender will signal a constant steering angle of 0 degrees. The correct steering angle will then only be indicated when the steering wheel has been turned more than 4.5 degrees.

ABS Control Module (w/EDL) -J104

ABS control module (w/EDL) -J104- is located under the floor mat in the front passenger's footwell.

Scheme 158

Replacing control module

1. Remove lower A-pillar trim. See «LOWER A-PILLAR TRIM, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__lower-a-pillar-trim-removing-and-installing) .
2. Remove floor mat.
3. Loosen bolts securing ABS control module (w/EDL) -J104-.
4. Unplug connector from ABS control module (w/EDL) -J104-.
5. Install new control module in reverse sequence.
6. Tightening torque for bolts: 9 Nm (80 in. lb)

For non-codable control module versions

Sender for rotation rate -G202- is located under the floor mat in the front left footwell.

Scheme 159

It measures the vehicle's rotation about the vertical axis (rotation rate).

1. To remove floor mat, first push left front seat back as far as it will go.
2. Remove lower section of A-pillar trim and sill molding. On LHD vehicles, remove foot support. See «INTERIOR TRIM»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim) .
3. Remove floor mat.
4. Tightening torque for bolt: 5 Nm (44 in. lb).

Sensor for transverse acceleration -G200- is located under the floor mat behind the seat cross member on the driver's side

Scheme 160

1. To remove floor mat, first remove driver's seat. See «FRONT SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames__front-seats) .
2. Remove lower section of A-pillar trim, sill molding and foot support. See «INTERIOR TRIM»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim) .
3. Remove floor mat.

Tightening torque for bolts: 5 Nm (44 in. lb).

For codable control module versions

Sender for rotation rate -G202- and sensor for transverse acceleration -G200- are combined in one housing.

The dual sensor (-G200-/-G202-) is located under the rear seat bench.

Scheme 161

1. Remove rear seat bench See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .

1. Unscrew both nuts.
2. Flip back protective housing and disconnect connector.
3. Loosen both bolts and remove sensor from mounting plate.

Tightening torque for bolts and nuts: 5 Nm (44 in. lb)

Scheme 162

Parking brake switch

The parking brake switch informs ABS control module (w/EDL) -J104- whether or not the parking brake is applied. This information is required because the parking brake influences the ESP control function.

ABS solenoid valve relay -J106- and ABS return flow pump relay -J105

The ABS solenoid valve relay -J106- and ABS return flow pump relay -J105- are now located in the relay carrier below the driver's-side storage compartment.

Warning light functions table

1. If the On Board Diagnostic (OBD) detects a malfunction in the system, it will be displayed by the warning lights when the ignition is switched on. Warning lights are located in the instrument cluster.

Instrument cluster without driver information display

1. The illustration shows ABS warning light -K47- (right arrow), warning light for brake system -K118- (center arrow, red symbol "brake system malfunction(" and the traction control indicator light -K86- (left arrow).

Scheme 163

Instrument cluster with driver information display

1. Warning light for brake system -K118- is not installed for instrument clusters with driver information display. The red symbol "brake system malfunction" appears on the display.
2. If the brake system is not fully functional, but the ABS warning light -K47- and the brake system warning symbol do not come on, this means the malfunction must be sought in the conventional braking system (mechanical/hydraulic components).

Scheme 164

Scheme 165

Scheme 166

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 167

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To check DTC memory, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .
3. For read measuring value block display group 2, see «READ MEASURING VALUE BLOCK: DISPLAY GROUP 2»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
4. To check zero position of steering angle sensor -G85-, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
5. For read measuring value block display group 5, see «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 168

1. To check DTC memory, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .
2. To check basic setting, see «ESP, CHECKING VIA ROAD TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-checking-via-road-test) .
3. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 169

1. To check DTC memory, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .
2. To check basic setting, see «ESP, CHECKING VIA ROAD TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-checking-via-road-test) .

Scheme 170

1. To check DTC memory, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .

Scheme 171

1. To check DTC memory, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 172

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

The On Board Diagnostic (OBD) function of the ESP can detect a total of 41 different malfunctions.

Note. If a malfunction is detected by the On Board Diagnostic (OBD) function, the system concerned switches itself off automatically for the duration of the current driving cycle. This is indicated by the relevant warning light in the instrument cluster. For further details refer to the section on WARNING LIGHT FUNCTIONS and WARNING LIGHT FUNCTIONS TABLE .

Note. The above does not apply to the DTC "01119 Gear recognition signal". See DIAGNOSTIC TROUBLE CODE (DTC) TABLE; DTC'S 00000 TO 00526 . If this malfunction is detected, none of the warning lights will come on. This malfunction affects the system's ability to recognize whether a forward or reverse gear is engaged; it can be compensated by ABS control module (w/EDL) -J104- via plausibility criteria.

The various control functions are inactive when VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool is connected and communication has been established with ABS control module (w/EDL) -J104-. The ABS warning light -K47-, the traction control indicator light -K86- and the brake system warning symbol will come on.

The system performs a self-test routine when the ignition is switched on before every trip. This process is indicated by the yellow ABS warning light -K47- and the traction control indicator light -K86-. The warning lights will go out after about 3 seconds. The self-test routine continues for a short time when the vehicle is moving, as some malfunctions can only be detected above a certain speed.

During the self-test process there will be audible noise from the valves and relays and from the return flow pump and the priming pump in the hydraulic unit. There will also be a slight pulsation at the brake pedal (usually at about 6 km/h).

Note. This is unavoidable, and is not a malfunction which requires repair.

1. DTC memory Permanent memory: contents remain intact when power supply is interrupted.
2. Data output Rapid data transfer (operating mode 1) The ABS warning light -K47-, the brake system warning symbol and the traction control indicator light -K86- come on in the dashboard if a malfunction is detected and the affected system is switched off. Functions 01 - Check Control Module Versions. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 02 - Check DTC Memory. See «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) . 03 - Output Diagnostic Test Mode. See «OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 04 - Basic setting. See «ESP, CHECKING VIA ROAD TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-checking-via-road-test) . 05 - Erase DTC memory. See «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 06 - End Output. See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) . 07 - Code Control Module. See «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 08 - Read Measuring Value Block. See «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) . 11 - Login procedure. See «PERFORMING LOGIN»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__performing-login) . Use VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool to perform On Board Diagnostic (OBD).

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Note. The following instructions describe the diagnostic procedure for VAG 1551 scan tool. The procedure when using VAS 5051 vehicle diagnostic, testing and information system is similar.

1. Go to start position of program by pressing --> button

Indicated on display

Scheme 173

1. Press buttons -0- and -1- for the function "Check Control Module Versions" and confirm entry with -Q- button.

Note. Also refer to the Parts List for the correct ABS control module (w/EDL) -J104- for the vehicle.

Scheme 174

Indicated on display (Allrad = all wheel drive)

Index 1): Indicates Part No. with control module index.

Index 2): Indicates system designation.

Index 3): Indicates hardware and software status.

Control module versions

CONTROL MODULE VERSIONS

Vehicles manufactured from January 1999 onward must be equipped with ABS control module (w/EDL) -J104-, Part No. 8D0 907 389 A/D/E. These control units are codable. New control modules supplied as replacement parts are uncoded and must be coded after installation.

Control modules with Part No. 4B0 907 389 cannot be coded.

The coding of the ESP control module serves to adapt the control module to the vehicle.

Coding is only possible after the workshop code (WSC) has been entered into VAG 1551 scan tool.

Note. If the control module is coded with the coding 00000 or a code number that is not correct for the vehicle, the ABS warning light -K47- and the ESP control lamp -K155- will come on continuously and the DTC01044 (control module incorrectly coded) will be stored in the DTC memory of the control module.

Performing login

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Indicated on display

Scheme 175

1. Press button -1- twice to select function "Login procedure".

Indicated on display

Scheme 176

1. Confirm entry with -Q- button.

Indicated on display

Scheme 177

1. Enter the required code number according to the following table and confirm entry with -Q- button.

ESP login table (A6)

ESP LOGIN (A6)

ESP login table (A6 Allroad All Wheel Drive)

ESP LOGIN (A6 ALLROAD ALL WHEEL DRIVE)

Coding control module

Indicated on display

Scheme 178

1. Press buttons -0- and -7- to select function "Code Control Module" and confirm with -Q- button.

Indicated on display

Scheme 179

1. Press -Q- button to confirm input.

Indicated on display

Scheme 180

1. Enter the required code number according to the following table and confirm entry with -Q- button.

ESP coding table (A6)

ESP CODING (A6)

ESP coding table (A6 Allroad quattro)

ESP CODING (A6 ALLROAD QUATTRO)

The display on VAG 1551 scan tool will show the control module identification: for example 8D0 407 398D ABS/ESP front

Scheme 181

Note. If the control module is coded with code 00000 or with a code that does not match the vehicle, the ABS Warning Light -K47- and the Traction Control Indicator Light -K86- remain continuously lit, and the DTC 01044 - Control module incorrectly coded - is stored in DTC memory of the control module.

1. Press --> button.
2. The zero position adjustment for steering angle sensor -G85- must also be performed.

Indicated on display

Scheme 182

1. Turn the steering wheel one turn to the right, turn one turn to the left beyond center, and then hold the wheel in the straight-ahead position.
2. Press button -1- twice to select function "Log-in procedure".

Indicated on display

Scheme 183

1. Press -Q- button to confirm input.

Indicated on display

Scheme 184

1. Enter code number 40168 and confirm entry with -Q- button.

Indicated on display

Scheme 185

1. Press buttons -0- and -4- to select function "Basic setting".

Indicated on display

Scheme 186

1. Press -Q- button to confirm input.

Indicated on display

Scheme 187

1. Press buttons -0-, -0- and -1- to input display group number 001.
2. Press -Q- button to confirm input.

If (Scheme 190) display appears, this means the function "Login procedure" has not been performed successfully.

Scheme 188

Indicated on display

Scheme 189

1. Check zero position via Function 08 "Read Measuring Value Block". See «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) , «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 190

Scheme 191

1. (Scheme 192) shows brake caliper type FN3 manufactured by Teves/Ate (identification: retaining spring clip on brake carrier).
2. (Scheme 193) shows brake caliper type HP2 manufactured by Lucas (identification: dual piston housing).
3. (Scheme 194) shows brake type FNRG 60 made by ATE (recognized by: large single-piston floating caliper).

The control module can transfer test data (measured values) to VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool. These measured values can provide information about the operational condition of the system and the sensors connected to it. In many cases the data supplied can be used to help trace and repair malfunctions The measured values provided by the ESP are grouped in six Display Groups, which can be called up via Display Group numbers.

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Note. When the printer is switched on, the contents of the display will be printed out on the scan tool log. When reading measured value block, also check wiring and connectors for intermittent loose contacts.

1. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and Press --> button.

Indicated on display

Scheme 192

1. Press buttons -0- and -8- for the function "Read Measuring Value Block".

Indicated on display

Scheme 193

1. Press -Q- button to confirm input.

Indicated on display

Scheme 194

1. Press buttons -0-, -0- and -1-.
2. Press -Q- button to confirm input.

Note. Display zones 1 to 4 show the actual wheel speeds (at the tire circumference) in km/h. These are calculated by ABS control module (w/EDL) -J104- on the basis of the signals received from the wheel speed sensors. If one of the display zones shows no reading, proceed as for DTC's 00283, 00285, 00287, 00290 "Speed sensor". See DIAGNOSTIC TROUBLE CODE (DTC) TABLE; DTC'S 00000 TO 00526 . In order to check that the speed sensor signals are correctly assigned to the four wheels, the vehicle must be raised. On vehicles with manual transmission put the gear shift in neutral. On vehicles with automatic transmission move the selector lever to position "N". Turn the relevant wheel by hand, and at the same time prevent the other driven wheels from rotating. When the vehicle is accelerated uniformly on a dry surface, the displayed values will increase continuously in rising whole numbers (e.g. to 6km/h, 7km/h, 8 km/h...). The difference between displayed values 1 to 4 should be not be more than +/- 1 km/h(error from out-of-round-wheels). If the values jump (for instance from 6km/h, 7km/h, to 12 km/h...) or if the difference between the displayed values is greater than +/- 1 km/h, then check the installation of the wheel speed sensors and rotors.

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing "upparrow "and" downarrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

Scheme 195

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 196

1. Press buttons -0-, -0- and -2-.
2. Press -Q- button to confirm input.

Read measuring value block: display group 2

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing "uparrow "and" downarrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

Scheme 197

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For DTC table, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 198

1. Press buttons -0-, -0- and -3-.
2. Press -Q- button to confirm input.

Note. For Display Group 3: If you wish to read out the display zones for engine speed and actual engine torque with the engine running, you must first interrupt the diagnostic link between the scan tool and the control module using the function "End Output". See ENDING OUTPUT . Then start the engine and set up the diagnostic link between scan tool and control module once again.

Indicated on display

Scheme 199

1. Press buttons -0- and -8- for the function "Read Measuring Value Block".
2. Press -Q- button to confirm input.

Indicated on display

Scheme 200

1. Press buttons -0-, -0- and -3-.
2. Press -Q- button to confirm input.

Read measuring value block: display group 3

Note. The On Board Diagnostic (OBD) is terminated by ABS control module (w/EDL) -J104- if road speed exceeds 19 km/h. If the Torque reduction value is subtracted from the Engine torque value, the result is Engine torque - actual (referred to as MMI)

Scheme 201

1. For DTC table, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing" uparrow "and" downarrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 202

1. Press buttons -0-, -0- and -4-.
2. Press -Q- button to confirm input.

Note. For Read measuring value block: display group 4 On control modules with Part No. 4D0 907 389 (without index letter), display group No. 4 is vacant, and cannot be selected by pressing buttons -1- and -3- on VAG 1551 scan tool or buttons uparrow and downarrow on VAG 1552 scan tool. If you try to select Display Group No. 4, the display will show

Indicated on display

Scheme 203

1. Press --> button.

Scheme 204

Indicated on display

If you do not wish to exit from the function "Read Measuring Value Block" you must avoid selecting Display Group No. 4: press button -C- and select Display Group No. 3 or 5 directly by entering the respective number.

Read measuring value block: display group 4

Note. The On Board Diagnostic (OBD) is terminated by ABS control module (w/EDL) -J104- if road speed exceeds 19 km/h.

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing "up arrow "and" down arrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

Scheme 205

1. For notes on the EDL, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. For DTC table, see «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 206

1. Press buttons -0-, -0- and -5-.
2. Press -Q- button to confirm input.

Note. For Display Group 5

1. If you wish to read out the display zones for rotation rate and lateral acceleration while the vehicle is moving, you must first break off the diagnostic link between the scan tool and the control module using the function "End Output". See «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) . Then start the engine and set up the diagnostic link between scan tool and control module once again.

Indicated on display

Scheme 207

1. Press buttons -0- and -8- for the function "Read Measuring Value Block".
2. Press -Q- button to confirm input.

Indicated on display

Scheme 208

1. Press buttons -0-, -0- and -5-.
2. Press -Q- button to confirm input.

Read measuring value block: display group 5

Note. The On Board Diagnostic (OBD) is terminated by ABS control module (w/EDL) -J104- if road speed exceeds 19 km/h.

Scheme 209

If the steering angle sensor is OK, a display will follow even if a zero position adjustment was not performed.

If no display appears, press button -C-, select Function 02 and Check DTC Memory. Repair malfunction according to DTC table . See ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING .

Note. The lateral acceleration sender and the combined sender for rotation rate and lateral acceleration are very sensitive to impacts. If one of these sensors is dropped by accident it must not be installed in the vehicle: install a new sensor.

Sensor for transverse acceleration -G200

Scheme 210

1. Remove the sender (or the combined sender for rotation rate and lateral acceleration) in order to test it.
2. Take out the rear seat bench. Unscrew bolts and detach control module for ultra-sound sensors -J347- and then the sender.
3. Leave the connector plugged in, and turn the sender 90° about its longitudinal axis in relation to its normal installed position.

This should give a reading of - 9.8 +/- 1 m/s 2 or + 9.8 +/- 1 m/s 2 on the scan tool in Display Group 5 of the function "Read Measuring Value Block".

A positive (+) reading will be indicated when the sender is subjected to lateral acceleration in a left-hand corner.

A negative (-) reading will be indicated when the sender is subjected to lateral acceleration in a right-hand corner.

1. When installing, tighten bolts securing sensor for transverse acceleration -G200- or combined sender for rotation rate and lateral acceleration to 5 Nm (44 in. lb).
2. Tighten bolts securing control module for ultra-sound sensors -J347- to 2 Nm (18 in. lb).

Note. Due to an error in test card 8.0 for VAG 1551 scan tool and test card 5.0 for VAG 1552 scan tool, the value displayed in the measured value block (Display group 5, Display zone 4) is reduced by a factor of ten. In other words a lateral acceleration of 9.81 m/s 2, for example, is indicated incorrectly as 0.98 m/s 2.

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing "uparrow "and" downarrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 211

1. Press buttons -0-, -0- and -6-.
2. Press -Q- button to confirm input.

Read measuring value block: display group 6

Note. The display group numbers can be selected in sequence by pressing buttons -1- and -3- ((VAG 1551 scan tool) or buttons uparrow and downarrow ((VAG 1552 scan tool) or by pressing "uparrow "and" downarrow" on the screen of VAS 5051 vehicle diagnostic, testing and information system.

Scheme 212

1. For function 11 login procedure, see «PERFORMING LOGIN»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__performing-login) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

1. Press button -C- in order to enter the display group number manually.

Indicated on display

Scheme 213

1. Press buttons -1-, -2- and -5-.
2. Press -Q- button to confirm input.

Note. For Read measuring value block: display group 125

1. On vehicles with control module No. 4B0 907 389, Display Group No. 125 is vacant, and cannot be selected either directly by entering a number, or by pressing buttons -1- and -3- on VAG 1551 scan tool or buttons uparrow and downarrow on VAG 1552 scan tool.
2. If you try to select Display Group No. 125, the display will show

Indicated on display

Scheme 214

1. Press --> button.

Indicated on display

Scheme 215

Scheme 216

If the steering angle sensor is OK, it sends information, even if a zero position adjustment has not yet been performed after replacement.

Note. The On Board Diagnostic (OBD) is terminated by ABS control module (w/EDL) -J104- if road speed exceeds 19 km/h.

Read measuring value block: display group 126

Note. Measuring value block 126 is only valid for A6 Allroad!

Scheme 217

The Output Diagnostic Test Mode enables you to check the function of the final control elements, which are the actuators (e.g. solenoid valves, relays or pump motors) energized by the control module after processing the incoming signals from the sensors.

Note. Output Diagnostic Test Mode can only be performed on vehicles with control modules No. 8D0 407 389 A/D/E. Output Diagnostic Test Mode is not possible for vehicles with control module No. 4B0 907 389. When the ignition is switched on, the Output Diagnostic Test Mode procedure should only be performed once; it cannot be repeated while the ignition is on.

The function of the final control elements includes all functions and properties of the final control elements under operating conditions, for example

1. An electrically operated hydraulic valve which opens and closes when activated by the control module.
2. The relay of an electric motor which starts the motor when activated by the control module. The motor should then run and deliver the required power.

It is advantageous to ensure that there are no electrical malfunctions in the system to be tested. This will enable you to recognize mechanical malfunctions. Perform a targeted troubleshooting procedure before the OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03) .

When you have made sure that there are no electrical malfunctions in the system, you will be able to identify any mechanical malfunctions in the individual control elements (actuators) if the results of the diagnosis are not as specified on the following pages. In this case, replace the affected component.

With the Bosch 5.3 ABS/ESP system the Output Diagnostic Test Mode enables you to check the electrically actuated hydraulic valves and the pump motor in the hydraulic control module. You can also check that the brake lines going to the four wheels are connected correctly.

Note. The vehicle must be raised until all wheels are free to turn. A second technician is required to check whether the wheels are locked or can be turned. The -C- button can be used to exit from the test sequence at any time. To avoid overloading the final control elements they are only actuated during the test sequence for a period of 60 (or 90) seconds. The final control test will be terminated if the --> button is not pressed within this period. The ABS/EDL warning light and the brake system warning symbol flash during the Output Diagnostic Test Mode. If the brake pedal is pressed repeatedly this will exhaust the vacuum in the brake servo. For this reason, the brake pedal must be pressed harder in order to achieve the same braking effect. It may be advisable to start the engine briefly to build up vacuum in the servo.

When you perform the function "Output Diagnostic Test Mode" the individual test steps are shown in the second line of the display on VAG 1551 scan tool. The following abbreviations are used

I = Inlet valve

O = Outlet valve

FL = Front Left

FR = Front Right

RL = Rear Left

RR = Rear Right

VBAT = Battery voltage at valve

0V = 0 Volt; No voltage at valve

Locked/free = Wheel condition; must be checked by 2nd technician

Hydr-P = Hydraulic pump

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__check-control-module-versions-function-01) and press --> button.

Indicated on display

Scheme 218

1. Press buttons -0- and -3- for the function "Output Diagnostic Test Mode".

Indicated on display

Scheme 219

1. Press -Q- button to confirm input.

Indicated on display

ABS return flow pump -V39- should start running audibly.

When you put your foot on the brake pedal you can feel it vibrating. (Scheme 224) This is because the hydraulic pump is producing pressure pulses in the brake lines, which induce the vibrations that can be felt at the pedal.

Scheme 220

The pressure pulses in the brake lines are not sufficient to lock the wheels.

(Scheme 225) is a schematic diagram of the hydraulic circuit of an ABS/EDL system. This will give a better understanding of the various test steps in the Output Diagnostic Test Mode.

1. The grey-shaded components are active.
2. Thin solid lines represent hydraulic lines or hoses which are not under pressure.
3. Thick broken lines represent hydraulic lines or hoses working as suction lines.
4. Thick solid lines represent hydraulic lines or hoses which are under pressure.

Scheme 221

1. Press --> button.

Indicated on display

Scheme 222

1. Press --> button.

Indicated on display

Scheme 223

When you press the brake pedal, brake fluid pressure will be built up in all four wheel brake cylinders. (Scheme 228) All four wheels will be locked.

This assumes that the mechanical and hydraulic components of the brake system are working properly, which means that the master cylinder is able to build up pressure in all four wheel brake cylinders and there are no leaks in the hydraulic lines, hoses and connections.

Scheme 224

If the wheels do not lock, perform a visual inspection of the brake fluid reservoir, the master cylinder, the hydraulic unit and the wheel cylinders.

Scheme 225

To start with, however, concentrate on the left front wheel. The function of the control elements for this wheel is tested first.

Note. This test step in the Output Diagnostic Test Mode corresponds to the pressure build-up phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 226

Keep pressing the brake pedal.

The inlet valve is activated, which interrupts the brake line. (Scheme 231) However, the fluid pressure is still maintained in the wheel cylinder. The left front wheel remains locked.

Scheme 227

Note. This test step in the Output Diagnostic Test Mode corresponds to the maintain pressure phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 228

Keep pressing the brake pedal. The inlet valve and the outlet valve for the left front wheel are activated. (Scheme 233) The hydraulic pump starts running and reduces the fluid pressure in the wheel cylinder via the open outlet valve.

Scheme 229

The brake pedal must not give, and should press back harder against your foot.

You should now be able to turn the left front wheel.

If you cannot turn the wheel, check whether the brake line for the left front wheel is correctly connected.

If this is the case, this indicates that there is a mechanical malfunction in one of the valves, providing that there is no electrical malfunction in the system. Replace the hydraulic control module.

Scheme 230

If the brake pedal gives under your foot, this means that the inlet valve or the non-return valve connected in parallel with the inlet valve is leaking. Replace the hydraulic control module.

Note. This test step in the Output Diagnostic Test Mode corresponds to the pressure reduction phase during ABS-controlled braking.

1. Press --> button.

Indicated on display

Scheme 231

ABS return flow pump -V39- will stop running.

Keep pressing the brake pedal. Only the inlet valve is now activated, and this interrupts the brake line. (Scheme 236) If the inlet valve is not leaking you should be able to turn the front left wheel.

Scheme 232

If you cannot turn the wheel, this means that the inlet valve or the non-return valve connected in parallel with the inlet valve is leaking. Replace the hydraulic control module.

1. Press --> button.

Indicated on display

Scheme 233

Keep pressing the brake pedal. The inlet valve is no longer activated and does not interrupt the brake line. (Scheme 238) The brake pedal will give perceptibly under your foot. Fluid pressure is built up again in the front left wheel cylinder. The wheel will be locked.

Scheme 234

1. Press --> button.

Indicated on display

Scheme 235

1. Press --> button.

Continue the Output Diagnostic Test Mode in order to check the right front, left rear and right rear wheels in turn. The test steps are the same as for the left front wheel, so they are not described in detail.

Indicated on display

Scheme 236

1. Press --> button.

Indicated on display

Scheme 237

1. Press --> button.

Indicated on display

Scheme 238

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 239

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 240

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 241

1. Press --> button.

Indicated on display

Scheme 242

1. Press --> button.

Indicated on display

Scheme 243

1. Press --> button.

Indicated on display

Scheme 244

1. Press --> button.

Indicated on display

Scheme 245

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 246

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 247

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 248

1. Press --> button.

Indicated on display

Scheme 249

1. Press --> button.

Indicated on display

Scheme 250

1. Press --> button.

Indicated on display

Scheme 251

1. Press --> button.

Indicated on display

Scheme 252

1. Press --> button.

ABS return flow pump -V39- should start running.

Brake pedal must not give.

Indicated on display

Scheme 253

1. Press --> button.

ABS return flow pump -V39- will stop running.

Indicated on display

Scheme 254

1. Press --> button.

Brake pedal should give perceptibly.

Indicated on display

Scheme 255

1. Press --> button.

Indicated on display

Scheme 256

1. Press --> button.

Indicated on display

Scheme 257

The EDL change-over valve (left) and the EDL inlet valve are activated. ABS return flow pump -V39- runs for one second. (Scheme 262) The pump draws brake fluid out of the fluid reservoir via the EDL inlet valve, and builds up pressure in the EDL-controlled wheel cylinders. These wheels will then be locked.

Scheme 258

If this is not the case, this indicates that there is a mechanical malfunction in one of the valves, provided that there are no electrical malfunctions in the system. Replace the hydraulic control module.

1. Press --> button.

Indicated on display

Scheme 259

Note. The Output Diagnostic Test Mode is completed. The ABS/EDL warning light and the brake system warning light go out.

1. Press --> button.

Indicated on display

Scheme 260

Note. If the ABS/EDL warning light does not go out, this indicates a malfunction in the system. Keep exactly to the specified test sequence. See TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES .

1. Press buttons -0- and -6- for the function "End Output" and confirm entry with the -Q- button.

Basic setting (scan tool function 04)

Initiating "Basic Setting" function 04 does the following for ESP

Zero position adjustment of steering angle sensor -G85

Before you can zero the sensor, you must have successfully carried out the "Login Procedure" function 11 using the VAG1551/1552 scan tool and the ABS control module -J104- must be coded. See CODE CONTROL MODULE (FUNCTION 07) ..

Hydraulic pump for traction control -V156-, activating

Activation of the hydraulic pump for traction control -V156- does not require any preparations. It is used to bleed the hydraulic system. See HYDRAULIC PUMP FOR TRACTION CONTROL -V156-, ACTIVATING .

ESP, checking via road test

The ESP driving test is used to test the plausibility of the signals from the sensor for transverse acceleration, yaw sensor and press sensor. See ESP, CHECKING VIA ROAD TEST .

Zero position adjustment of steering angle sensor -G85

Note. Zero position compensation of steering angle sensor -G85- must be performed with an accuracy of + 5 degrees.

Zero position adjustment

Zero position compensation of steering angle sensor -G85- is necessary in the following cases

1. If ABS control module (w/EDL) -J104-, steering angle sensor -G85- or the steering column are replaced
2. After performing coding of ABS control module (w/EDL) -J104-.
3. If suspension or steering geometry is adjusted when checking wheel alignment.
4. If there is a code in the DTC memory of ABS control module (w/EDL) -J104- and the instructions in the DTC table require the zero position compensation to be carried out.

1. Start engine.
2. Turn steering wheel one turn to the right and one turn to the left.
3. Perform a short road test: drive in a straight line on a level surface at a speed not higher than 20 km/h.

If the steering wheel is properly centered (road test)

1. Bring the vehicle to a standstill - still keeping it in a straight line.
2. Perform zero position compensation. See «ESP, CHECKING VIA ROAD TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-checking-via-road-test) .
3. Take care not to move the steering wheel from this point onward.
4. Do not switch off the ignition.

If the steering wheel is not properly centered

1. Make the necessary adjustments by checking wheel alignment. See «SPECIFICATIONS & PROCEDURES»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures) . If the steering geometry has to be checked, center the steering as instructed by electronic wheel alignment equipment (i.e. set front wheels accurately to straight-ahead position). Now perform zero position compensation. See «HYDRAULIC PUMP FOR TRACTION CONTROL -V156-, ACTIVATING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__hydraulic-pump-for-traction-control-v156) . Take care not to move the steering wheel from this point onward.
2. Do not switch off the ignition.
3. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Indicated on display

Scheme 261

1. Press button -1- twice to select function "Login procedure".

Indicated on display

Scheme 262

1. Press -Q- button to confirm input.

Indicated on display

Scheme 263

1. Enter code number 40168 and confirm entry with -Q- button.

Indicated on display

Scheme 264

1. Press buttons -0- and -4- to select function "Basic setting".

Indicated on display

Scheme 265

1. Press -Q- button to confirm input.

Indicated on display

Scheme 266

1. Press buttons -0-, -0- and -1-.
2. Press -Q- button to confirm input.

If (Scheme 271) display appears, this means the function "Login procedure" has not been performed successfully.

Scheme 267

Indicated on display

Scheme 268

1. Check zero position via Function 08 "Read Measuring Value Block". See «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) , «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Or

Indicated on display

Scheme 269

1. Check DTC Memory. See «ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-diagnostic-trouble-code-dtc-memory) .
2. Erase DTC memory. See «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. Switch off ignition.
4. Switch on ignition.
5. Perform zero position compensation once again.
6. Go to start position of program by pressing --> button

Indicated on display

Scheme 270

Or

Indicated on display

Scheme 271

You have forgotten to turn the steering wheel one turn to the right and one turn to the left.

1. Switch off ignition.
2. Switch on ignition.
3. Perform zero position compensation once again.
4. Go to start position of program by pressing --> button

Indicated on display

Scheme 272

Hydraulic pump for traction control -V156-, activating

Activation of the hydraulic pump for traction control -V156- (ESP) serves to bleed the hydraulic system.

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Indicated on display

Scheme 273

1. Press buttons -0- and -4- to select function "Basic setting".

Indicated on display

Scheme 274

1. Press -Q- button to confirm input.

Indicated on display

Scheme 275

1. Press buttons -0-, -0- and -2-.
2. Press -Q- button to confirm input.

Indicated on display

Scheme 276

Note. Hydraulic pump for traction control -V156- (ESP) will be activated for 10 seconds.

1. Press --> button to end function.

Indicated on display

Scheme 277

ESP, checking via road test

The ESP road test serves to check the plausibility of the signals from the lateral acceleration sender, rotation rate sender and pressure sender.

The ESP road test should always be carried out after removing or replacing any parts of the ESP system.

Note. The ESP road test can only be performed on vehicles with control module No. 8D0 407 389 D / 8D0 407 389 E. It is not possible to cancel the ESP road test after it has been started. The complete test procedure must be performed.

1. Connect VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .

Indicated on display

Scheme 278

1. Press buttons -0- and -4- to select function "Basic setting".

Indicated on display

Scheme 279

1. Press -Q- button to confirm input.

Indicated on display

Scheme 280

1. Press buttons -0-, -0- and -3-.
2. Press -Q- button to confirm input.

Indicated on display

Scheme 281

Note. The ESP road test is activated. The ABS warning light -K47- and traction control indicator light -K86- will come on.

1. Press buttons -0- and -6- for the function "End Output" and confirm entry with the -Q- button.

Indicated on display

Scheme 282

1. Disconnect VAG 1551 scan tool.
2. Start engine.
3. Press brake pedal firmly (brake pressure higher than 35 bar) until traction control indicator light -K86- goes out.

Note. This completes calibration in the stationary condition.

1. Perform the following road test

Note. Please drive according to traffic conditions and remember that road safety must be given first priority at all times.

1. Drive the vehicle through a right turn, then a left turn (or vice versa).

Note. A rotation rate (turning rate) of approx. 10° per second must be reached when driving the vehicle through the left and right turns during the test. This can be done, for instance, by driving through a turn with a radius of 10 to 12 meters at a speed of 15 to 20 km/h for about 4 seconds. The vehicle must be driven in such a way that the ESP, ASR, EDL and ABS functions are not activated. If other maneuvers are necessary between the two required turns because of traffic conditions, this will have no influence on the result of the ESP road test.

The ABS warning light -K47- should now go out. The ESP road test is now completed, and the system is OK.

If the ABS warning light -K47- does not go out, this means the ESP road test has not been performed properly.

If the ABS warning light -K47- does not go out and the traction control indicator light -K86- comes on again, this means there is a malfunction in the system; Check DTC Memory. See ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING .

Note. If the ESP road test is interrupted (for instance by switching off the ignition) it will be necessary to repeat the complete test procedure.

1. If the On Board Diagnostic (OBD) does not give any indication of the source of the malfunction, work through the complete Electrical testing.
2. If the On Board Diagnostic (OBD) provides a direct indication of the source of the malfunction, only carry out the test steps recommended in the DTC table (specific testing).

Requirements for test

1. An Automatic test sequence must first be performed to establish that any malfunctions present in the transmission and engine control modules can only originate from the ABS.

1. Connect VAG 1551 scan tool and select address word 00 with ignition switched on. See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
2. After completing the Electrical testing, check and erase the DTC memories of the transmission and engine control modules.

1. The multi-pin connector between the wiring harness and ABS control module (w/EDL) -J104- must be in proper condition, without bent, broken or corroded contacts. Replace any damaged contacts using VAS 1978 wiring repair kit.

Scheme 283

Note. The instructions supplied with VAS 1978 wiring repair kit normally do not permit repairs to the wiring of the ABS and associated systems. However, this only applies to the screened wiring in the system.

1. Switch ignition and electrical consumers off before commencing the check (headlights, lighting, fan, etc.).
2. For test steps 13 to 16 raise the vehicle so that the wheels can turn freely. On vehicles with manual transmission put the gear shift in neutral. On vehicles with automatic transmission move the selector lever to position "N".

The following test equipment is required

1. VAG 1551 scan tool or VAG 1552 scan tool
2. VAG 1598 test box/20
3. VAG 1594 auxiliary test set
4. VAG 1526 tester hand-held multimeter
5. VAG 1310 A pressure gauge

Connecting VAG 1598 test box/20 and testing the ESP system

1. Switch off ignition.
2. Remove ABS control module (w/EDL) -J104- See «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

1. Unplug multi-pin connector from ABS control module (w/EDL) -J104
2. Check multi-pin connector between wiring harness and ABS control module (w/EDL) -J104-.

The socket designations on VAG 1598 test box/20 are identical with the contact designations on ABS control module (w/EDL) -J104- and the designations of the connector on the wiring harness

Scheme 284

1. Connect VAG 1598 test box/20 to multi-pin connector on harness.

Scheme 285

Scheme 286

Scheme 287

Scheme 288

Scheme 289

Scheme 290

Scheme 291

Scheme 292

Scheme 293

Scheme 294

Scheme 295

Note. For test table

1. The socket designations of the VAG 1598 test box are identical to the contact designations of the ABS control module (w/EDL) -J104- in the wiring diagram. Incorrect test procedures can cause damage to the system: do not make connections between any contacts other than those listed in the table

1. The specified values refer to the readings obtained on VAG 1526 tester and are not necessarily applicable for other test units.
2. If the readings obtained do not match the specifications, carry out the malfunction repair measures in the right-hand part of the table.

1. If the specified values are achieved, also check wiring for intermittent loose contacts and short circuit to positive and Ground (GND). This applies especially to sporadic malfunctions.
2. Use VAG 1594 test leads for checking continuity (bridging leads).
3. If the measured figures only differ slightly from the specifications, clean the sockets and plugs of the testers and test leads (with contact spray G 000 700 04 ) and repeat the check. Before replacing components, check wiring and connections again, particularly if the specification calls for a resistance reading of less than 10 ohms.

Scheme 296

Scheme 297

Scheme 298

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 299

Scheme 300

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 301

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 302

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 303

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 304

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 305

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 306

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 307

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 308

The output connections on ABS control module (w/EDL) -J104- are wired differently for the various different versions.

Scheme 309

Scheme 310

Scheme 311

Scheme 312

Scheme 313

Scheme 314

Scheme 315

Scheme 316

Scheme 317

Scheme 318

Scheme 319

Scheme 320

Scheme 321

Scheme 322

Scheme 323

Scheme 324

ESP Diagnostic Trouble Code (DTC) memory, checking

1. Make sure test requirements have been met. See «REQUIREMENTS FOR TEST»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__requirements-for-test) .
2. Connect VAG 1551 scan tool and select address word 03 for "Brake electronics". See «VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__vag-1551-scan-tool-connecting-and) .
3. Check the control module version. See «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and Press --> button.
4. Press buttons -0- and -2- to select function "Check DTC Memory" and confirm with -Q- button.

Note. Every malfunction that can be detected by the system has a 5-digit DTC, which is listed in the left-hand column of the DTC table. The message identifying the malfunction and the DTC will be printed out on the printer of VAG 1551 scan tool if the PRINT button is pressed. The malfunction does not appear on the display of VAG 1551 scan tool. The contents of the DTC memory remains stored until the memory is erased. See ERASING DTC MEMORY . Sporadically occurring malfunctions are additionally identified as such, with "ISP" appearing on the right of the display. See ON BOARD DIAGNOSTIC (OBD) FOR ABS AND ESP, GENERAL NOTES . Static malfunctions which cannot be detected when the vehicle is stationary are also identified with "ISP" after the ignition has been switched off and then on again. The following table includes all the malfunctions which can be detected by the ABS control module (w/EDL) -J104- and displayed and printed out by VAG 1551 scan tool. Malfunctions are listed according to DTC's.

Scheme 325

1. For warning light functions, see «WARNING LIGHT FUNCTIONS TABLE»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__warning-light-functions-table) .
2. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 2»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 326

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group)
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 327

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 328

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 329

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 330

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 331

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) article.
2. For front wheel bearing replacement procedure, see «SUSPENSION - FRONT»(/audi/a6/c5-1997-2001/remont/suspension-front/#suspension-front) .
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
5. For control module identification, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 332

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) article.
2. For front wheel bearing replacement procedure, see «SUSPENSION - FRONT»(/audi/a6/c5-1997-2001/remont/suspension-front/#suspension-front) .
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
5. For control module identification, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 333

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) article.
2. For rear wheel bearing replacement procedure, see appropriate SUSPENSION - REAR article.
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 334

1. For information on brake system, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) article.
2. For rear wheel bearing replacement procedure, see appropriate SUSPENSION - REAR article.
3. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
4. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 335

Scheme 336

Scheme 337

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 338

Scheme 339

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. For control module identification, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 340

Scheme 341

Scheme 342

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. For information on replacing brake system components, see «DISC»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) and «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) articles.

Scheme 343

Scheme 344

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 345

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 6»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .
2. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 346

1. For function of ESP, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. To replace steering angle sensor -G85-, see «STEERING ANGLE SENSOR -G85-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
3. For login procedure, see «PERFORMING LOGIN»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__performing-login) .
4. To code control module, see «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
5. To perform zero compensation, see «ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__zero-position-adjustment-of-steering-angle) .

Scheme 347

1. For function of ESP, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. To perform zero compensation, see «ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__zero-position-adjustment-of-steering-angle) .

Scheme 348

1. For function of ESP, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. For measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 349

1. For steering angle sensor information, see «STEERING ANGLE SENSOR -G85-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
2. For login procedure, see «PERFORMING LOGIN»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__performing-login) .
3. To perform zero compensation, see «ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__zero-position-adjustment-of-steering-angle) .

Scheme 350

1. For steering angle sensor information, see «STEERING ANGLE SENSOR -G85-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
2. For wheel alignment information, see «SPECIFICATIONS & PROCEDURES»(/audi/a6/c5-1997-2001/remont/wheel-alignment/#specifications-procedures) .
3. For login procedure, see «PERFORMING LOGIN»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__performing-login) .
4. To perform zero compensation, see «ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__zero-position-adjustment-of-steering-angle) .

Scheme 351

1. To code ABS control module, see «CODE CONTROL MODULE (FUNCTION 07)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For function of ESP, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 352

Scheme 353

Scheme 354

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 355

Scheme 356

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 357

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 126»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 358

1. For read measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 126»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 359

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For information on replacing ABS control module, see «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 360

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For information on replacing ABS control module, see «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 361

1. For electrical testing, see «ELECTRICAL TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 362

1. For information on replacing ABS components, see «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 363

Scheme 364

1. For information on replacing ABS components, see «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 365

1. For information on replacing ABS components, see «ANTILOCK BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 366

1. For information on transverse acceleration sensor, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 367

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 368

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 369

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 370

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 371

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 372

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 373

1. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 374

1. For measuring value block, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 375

1. For zero position adjustment, see «BASIC SETTING (SCAN TOOL FUNCTION 04)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__basic-setting-scan-tool-function-04) .
2. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
4. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 376

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 377

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on transverse acceleration sensor, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 378

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 379

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on transverse acceleration sensor, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 380

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 381

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on transverse acceleration sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 382

1. For information on sender for rotation rate, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 383

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 384

Scheme 385

Scheme 386

1. For information on sender for rotation rate, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 387

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 388

1. For read measuring value block, display group 2, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) , «READ MEASURING VALUE BLOCK: DISPLAY GROUP 2»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For read measuring value block, display group 5, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) , «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 389

1. For information on hydraulic pump for traction control, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
2. For brake bleeding procedure, see «BLEEDING BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .

Scheme 390

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 391

Scheme 392

1. For information on hydraulic pump for traction control or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
2. For brake bleeding procedure, see «BLEEDING BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .

Scheme 393

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on hydraulic pump for traction control or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
5. For brake bleeding procedure, see «BLEEDING BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .

Scheme 394

Scheme 395

Scheme 396

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. For information on brake pressure/lateral acceleration sender or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .
4. For brake bleeding procedure, see «BLEEDING BRAKE SYSTEM»(/audi/a6/c5-1997-2001/remont/mechanical-hydraulic/#brake-system) .

Scheme 397

1. For basic setting, see «BASIC SETTING (SCAN TOOL FUNCTION 04)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__basic-setting-scan-tool-function-04) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 3»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 398

1. For measuring value block, display group 5, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 399

1. For basic setting, see «ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__zero-position-adjustment-of-steering-angle) .
2. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
3. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
4. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .

Scheme 400

Scheme 401

Scheme 402

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 403

Scheme 404

Scheme 405

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on rotation rate sender or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 406

Scheme 407

1. For measuring value block, display group 5, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 408

Scheme 409

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on rotation rate sender or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 410

1. For measuring value block, display group 5, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 5»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__read-measuring-value-block-display-group) .

Scheme 411

Scheme 412

Scheme 413

Scheme 414

1. To erase DTC memory, see «ERASING DTC MEMORY»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. To end output, see «ENDING OUTPUT»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__ending-output) .
3. To perform road test, see «ROAD TESTING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__road-testing) .
4. For information on lateral acceleration sender or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 415

1. For information on rotation rate sender or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 416

1. For measuring value block, display group 125, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 125»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 417

1. To check data bus wires, see «THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__three-or-more-control-modules-communicating) .

1. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 418

1. For measuring value block, display group 125, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 125»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 419

1. To check data bus wires, see «THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__three-or-more-control-modules-communicating) .
2. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 420

1. For measuring value block, display group 125, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 125»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 421

1. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For information on the steering angle sensor or ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 422

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 423

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. To check bus wires, see «TWO CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 424

1. For measuring value block, display group 125, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 125»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 425

1. To check data bus wires, see «THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__three-or-more-control-modules-communicating) .
2. For information on ABS control module, see «ABS/ESP SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-abs) .

Scheme 426

1. For measuring value block, display group 125, see «READ MEASURING VALUE BLOCK (FUNCTION 08)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) and «READ MEASURING VALUE BLOCK: DISPLAY GROUP 125»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .
2. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
3. To check data bus wires, see «THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__three-or-more-control-modules-communicating) .

Scheme 427

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. To check data bus wires, see «THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__three-or-more-control-modules-communicating) .

Scheme 428

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .
2. To check control module versions, see «CHECK CONTROL MODULE VERSIONS (FUNCTION 01)»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp) .

Scheme 429

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

Scheme 430

1. For ESP function, see «ESP, FUNCTION»(/audi/a6/c5-1997-2001/remont/anti-locktraction-control/#brake-system-on-board-diagnostic-obd-abs-esp__esp-function) .

On Board Diagnostic (OBD) is in Guided Fault Finding in VAS 5051

On Board Diagnostic (OBD) is only in Guided Fault Finding Using VAS 5051

See also:
• BLEEDING BRAKE SYSTEM
• ANTILOCK BRAKE SYSTEM
• BRAKELIGHT SWITCH
• SUSPENSION - FRONT
• LOWER A-PILLAR TRIM, REMOVING AND INSTALLING
• INTERIOR TRIM
• FRONT SEATS
• REAR SEATS
• SPECIFICATIONS & PROCEDURES
• VAG 1551 SCAN TOOL, CONNECTING AND ENTERING ADDRESS WORD
• SCAN TOOL FUNCTIONS, SELECTING
• REQUIREMENTS FOR TEST
• ERASING DTC MEMORY
• ENDING OUTPUT
• TROUBLESHOOTING ABS AND ESP, SAFETY PRECAUTIONS AND GENERAL NOTES
• WARNING LIGHT FUNCTIONS OVERVIEW
• CHECK CONTROL MODULE VERSIONS
• READ MEASURING VALUE BLOCK (FUNCTION 08)
• CODE CONTROL MODULE (FUNCTION 07)
• ELECTRICAL TESTING
• ABS, EDL AND ABS, EDL, ASR DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING
• OUTPUT DIAGNOSTIC TEST MODE (FUNCTION 03)
• TROUBLESHOOTING PROCEDURE
• ON BOARD DIAGNOSTIC (OBD) FOR ABS AND ESP, GENERAL NOTES
• ROAD TESTING
• BOSCH 5.3 ABS/EDL SYSTEM, FUNCTION
• WARNING LIGHT FUNCTIONS TABLE
• ESP DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING
• READ MEASURING VALUE BLOCK: DISPLAY GROUP 5
• ESP, CHECKING VIA ROAD TEST
• PERFORMING LOGIN
• ESP, FUNCTION
• HYDRAULIC PUMP FOR TRACTION CONTROL -V156-, ACTIVATING
• ZERO POSITION ADJUSTMENT OF STEERING ANGLE SENSOR -G85
• BASIC SETTING (SCAN TOOL FUNCTION 04)
• THREE OR MORE CONTROL MODULES COMMUNICATING VIA A CAN-BUS