Multiport Fuel Injection (mfi), Generic Scan Tool (4.2l v8 5v - Art, Awn, Bbd) Audi S6 C5

Safety precautions

To reduce the risk of personal injury and/or damage to the fuel injection and ignition system, always observe the following

1. Only disconnect and reconnect wires for injection and ignition system, including test leads, when ignition is turned off.
2. If engine is to be cranked at starting RPM without starting (for example, for compression testing), disconnect connector from ignition coils and from fuel injectors.
3. It is possible that the control module will recognize a malfunction and store a DTC during some tests. After completing all tests and repairs, DTC memory should therefore be checked and erased if necessary. Readiness code must be generated after DTC memory is erased. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Always switch ignition off before cleaning engine.

1. Note radio code (for vehicles equipped with coded anti-theft radio / radio navigation system), obtain if necessary.
2. Remove cover above the battery (arrows). NOTE: For vehicles without separate battery cover: Remove plenum chamber cover.
3. Disconnect battery Ground (GND) wire (arrow) with the ignition switched off.

Note. Be sure to activate vehicle features (radio/radio-navigation system, clock, electric window regulators) according to owner's manual when the battery is re-connected. Deactivate service mode of Telematics Control Module. See TELEMATICS, ON BOARD DIAGNOSTIC (OBD) . Generate readiness code. See READINESS CODE, GENERATING .

If test and measuring equipment is required during road test, note the following

Rules of cleanliness

When working on the fuel supply or fuel injection systems, the following "6 rules of cleanliness" should be carefully observed

1. Thoroughly clean all connections and the surrounding area before disconnecting.
2. Place parts that have been removed on a clean surface and cover. Use lint-free cloths only!
3. Carefully cover opened components or seal, if repairs are not performed immediately.
4. Only install clean components: Only unpack replacement parts immediately prior to installation. Do not use parts that have been stored loose (in tool boxes etc.)
5. When the system is open: Avoid working with compressed air. Do not move vehicle unless absolutely necessary.
6. Disconnected electrical harness connectors: Protect from dirt and moisture. Be sure harness connector is dry before connecting.

Technical data Audi A6

ENGINE IDENTIFICATION (A6)

Technical data Audi S6

ENGINE IDENTIFICATION (S6)

Overview of component locations

Components A through G are not depicted in the exploded view illustration.

1. Brake light switch -F- and brake pedal switch -F47- Component location. See «Component location of brake light switch -F- and brake pedal switch -F47-, clutch vacuum vent valve switch -F36»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-brake-light-switch) .
2. Diagnostic connector Located in knee bolster on driver's side
3. Fuel Pump (FP) Relay -J17- Component location. See «Component location Fuel Pump (FP) Relay -J17»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-fuel-pump-fp-relay) . Checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Motronic Engine Control Module (ECM) voltage supply relay -J271- Not installed on all construction versions Component location. See «Component locations in E-box, plenum chamber»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-locations-in-e-box-plenum-chamber) . Checking. See «CHECK MOTRONIC ENGINE CONTROL MODULE (ECM) POWER SUPPLY RELAY -J271- AND ACTIVATION»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
5. Throttle Position (TP) sensor -G79- and sender 2 for accelerator pedal position -G185- Component location. See «Component location, Throttle Position (TP) sensor -G79- and sender 2 for accelerator pedal position -G185»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-throttle-position-tp-sensor) . Checking. See «THROTTLE POSITION (TP) SENSOR, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) . When replacing, adapt kickdown function, to do so switch on ignition and press accelerator pedal all the way down past the kickdown point and hold in position for at least 20 seconds Removing and installing accelerator pedal module. See «ACCELERATOR PEDAL MODULE WITH THROTTLE POSITION (TP) SENSORS, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
6. Malfunction lamp for On Board Diagnostic (OBD)/Malfunction Indicator Lamp (MIL) -K83- ("MIL" Lamp) In instrument cluster; significance of lamp. See «MALFUNCTION LAMP FOR ON BOARD DIAGNOSTIC (OBD)/MALFUNCTION INDICATOR LAMP (MIL) -K83- IN INSTRUMENT CLUSTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__malfunction-lamp-for-on-board-diagnostic) .
7. Electronic Power Control (EPC) Warning Lamp -K132- ("EPC" lamp) In instrument cluster; significance of lamp. See «ELECTRONIC POWER CONTROL (EPC) WARNING LAMP -K132- IN INSTRUMENT CLUSTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__electronic-power-control-epc-warning-lamp) .

Note. The following list refers to (Scheme 538).

1. Evaporative Emission (EVAP) canister purge regulator valve -N80- Checking. See «CHECKING EVAPORATIVE EMISSION (EVAP) CANISTER PURGE REGULATOR VALVE -N80»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. 3-pin harness connector for Knock Sensor (KS) 1 -G61
3. 4-pin harness connector For Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29- Bank 1, sensor 2
4. 4-pin harness connector For Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- Bank 2, sensor 2
5. Mass Air Flow (MAF) sensor -G70- with Intake Air Temperature (IAT) sensor -G42- Checking. See «MASS AIR FLOW (MAF) SENSOR -G70-, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
6. 4-pin harness connector For Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19- Bank 1, sensor 1
7. Valve -1- for camshaft adjustment -N205- Checking. See «SOLENOID VALVES FOR CAMSHAFT ADJUSTMENT, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
8. Fuel pressure regulator Checking. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
9. Engine Coolant Temperature (ECT) sensor -G62- At coolant pipe behind cylinder head bank 1 with Engine Coolant Temperature (ECT) Sensor -G2- Checking. See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR -G62-, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__engine-coolant-temperature-ect-sensor-g62) . If necessary, release pressure in cooling system before removing
10. Throttle valve control module -J338- With throttle drive (power accelerator actuation) -G186-, angle sensor -1- for throttle drive (power accelerator actuation) -G187-, and angle sensor -2- for throttle drive (power accelerator actuation) -G188- Checking. See «THROTTLE VALVE CONTROL MODULE -J338-, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__throttle-valve-control-module-j338-checking) . When replacing, perform adaptation, for this purpose switch on ignition for at least 20 seconds without starting engine or depressing accelerator pedal
11. Secondary Air Injection (AIR) solenoid valve -N112- Component location. See «Component location of Secondary Air Injection (AIR) Solenoid Valve -N112»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-secondary-air-injection) . Checking. See «SECONDARY AIR INJECTION (AIR) SOLENOID VALVE -N112- CHECKING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
12. 4-pin harness connector For Heated Oxygen Sensor (HO2S) 2 -G108- and Oxygen Sensor (O2S) 2 Heater -Z28- Bank 2, sensor 2
13. 3-pin harness connector for Engine Speed (RPM) sensor -G28
14. Camshaft Position (CMP) Sensor 2 -G163- Bank 2 Component location. See «Component location of Camshaft Position (CMP) Sensor -G163»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-camshaft-position-cmp) . Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd__check-camshaft-position-cmp-sensor) .
15. Secondary Air Injection (AIR) pump relay -J299- Component location. See «Component locations in E-box, plenum chamber»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-locations-in-e-box-plenum-chamber) . Checking. See «SECONDARY AIR INJECTION (AIR) PUMP RELAY -J299- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
16. Motronic Engine Control Module (ECM) -J220- Component location. See «Component locations in E-box, plenum chamber»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-locations-in-e-box-plenum-chamber) . Checking voltage supply. See «Voltage supply for Engine Control Module (ECM), checking»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) . Removing and installing. See «ENGINE CONTROL MODULE (ECM), REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
17. Ignition coils with power output stages Bank 2 Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
18. 3-pin harness connector for Knock Sensor (KS) 2 -G66
19. Valve -2- for camshaft adjustment -N208
20. Intake Manifold Change-Over Valve -N156
21. Intake Manifold Tuning (IMT) Valve -2- -N261- On Audi S6: Intake Air Switch-over valve -N335
22. Camshaft Position (CMP) Sensor -G40- Bank 1 Component location. See «Component location of Camshaft Position (CMP) Sensor -G40»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-camshaft-position-cmp) . Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd__check-camshaft-position-cmp-sensor) .
23. Ignition coils with power output stages Bank 1 Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/s6/c5-1999-2004/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
24. Secondary Air Injection (AIR) Pump Motor -V101- Component location. See «Component location of Secondary Air Injection (AIR) Pump Motor -V101»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__component-location-of-secondary-air-injection) . Checking. See «CHECK VOLTAGE SUPPLY OF THE SECONDARY AIR INJECTION (AIR) PUMP MOTOR»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Component location, Throttle Position (TP) sensor -G79- and sender 2 for accelerator pedal position -G185

1. integrated in accelerator pedal module (arrow) NOTE: Throttle Position (TP) Sensor -G79- and Sender -2- for accelerator pedal position -G185- are integrated in the accelerator pedal module and cannot be replaced separately.

Component location Fuel Pump (FP) Relay -J17

1. located at position 4 of central electronics in driver's footwell, left

Component location of brake light switch -F- and brake pedal switch -F47-, clutch vacuum vent valve switch -F36

1. Clip
2. Brake light switch -F-, brake pedal switch -F47
3. Clutch vacuum vent valve switch -F36- NOTE: In order to assure sufficiently secure fitting, switches must not be installed more than once.

Removing and installing switch

See CLUTCH PEDAL POSITION (CPP) SWITCH-F 194-, REMOVING AND INSTALLING and BRAKELIGHT SWITCH .

Component locations in E-box, plenum chamber

1. Motronic Engine Control Module (ECM) -J220
2. Secondary Air Injection (AIR) pump relay -J299
3. Motronic Engine Control Module (ECM) Power Supply Relay -J271-; not installed on all versions
4. Fuse S130 for Secondary Air Injection (AIR) pump

Component location of Camshaft Position (CMP) Sensor -G40

1. At cylinder head bank 1 (right side), front (arrow).

Component location of Camshaft Position (CMP) Sensor -G163

1. At cylinder head bank 2 (left side), rear (arrow).

Component location of Secondary Air Injection (AIR) Solenoid Valve -N112

1. At rear on fuel rail pipe (arrow).

Component location of Secondary Air Injection (AIR) Pump Motor -V101

1. At front right in engine compartment below the longmember (arrow)

Fuel injectors, removing and installing

1. Remove engine cover (arrows).
2. Remove the air intake tube (arrows) between the air filter and the throttle valve part.
3. Disconnect vacuum hose from fuel pressure regulator.
4. Disconnect knock sensor harness connector -1- at left and right cylinder bank, remove cable tie if necessary.
5. Remove Secondary Air Injection (AIR) Solenoid Valve -N112- from fuel rail pipe.
6. Disconnect all harness connectors (arrows) at fuel injectors at left and right of cylinder bank.
7. Remove fuel rail with injectors from intake manifold uniformly upward and set aside in rear of engine compartment on a clean cloth. CAUTION: Fuel system is under pressure! Before opening system, place rags around the connection area. Then release pressure by carefully loosening connection.
8. Disengage retaining clip and remove fuel injector.

Installing

Installation is reverse of removal, noting the following

1. Replace O-rings at all opened connections.
2. Lubricate O-rings with clean engine oil.
3. Make sure fuel injectors are in place and seated correctly
4. Check clips for unobstructed fitting.
5. Place fuel rail with secured fuel injectors onto intake manifold, and apply uniform pressure to press it in.

Tightening torque

FUEL RAIL TO INTAKE MANIFOLD TIGHTENING TORQUE

Recommended special tools and equipment

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

Test requirements

1. Fuse for oxygen sensor heater OK
2. Ground (GND) connections at engine and transmission OK
3. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Ignition switched off.

Note. Voltage for Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1) and Oxygen Sensor (O2S) 2 Heater 2 -Z28- (bank 2, sensor 1) is supplied via the Fuel Pump (FP) relay. Bank 1 = cylinder bank 1 in direction of travel, right; Bank 2 = cylinder bank 2 in direction of travel, left. When servicing terminals in harness connector of Heated Oxygen Sensor (HO2S), use only gold-plated terminals.

Work procedure

1. Disconnect electrical 4-pin harness connector -3- at right from Heated Oxygen Sensor (HO2S) -G39- (before catalytic converter) and Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1).
2. Remove coolant reservoir -3- (arrows)
3. Disconnect wire from Engine Coolant Level (ECL) Warning Switch -F66- and lay coolant reservoir aside. NOTE: Coolant hoses -1- and -2- remain connected.
4. Disconnect electrical 4-pin harness connector at left (arrow) from Heated Oxygen Sensor (HO2S) 2 -G108- (before catalytic converter) and Oxygen Sensor (O2S) 2 Heater 2 -Z28- (bank 2, sensor 1).

Checking internal resistance

1. Connect multimeter between terminal 3 and 4 for resistance measurement. Specified value at room temperature: 2 to 10 ohms.

If specified value is not obtained

1. Replace respective oxygen sensor before catalytic converter. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If specified value is obtained

Checking voltage supply

1. Connect multimeter between terminal 1 (B+) and 2 (Ground -GND-) for voltage measurement.
2. Operate starter briefly. Specified value: approx. battery voltage.
3. Switch ignition off.

If there is no voltage

1. Connect multimeter for voltage measurement as follows: HO2S (BEFORE TWC) HEATER CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
2. Operate starter briefly. Specified value: approx. battery voltage.
3. Switch ignition off.

If there is no voltage again

1. Check wire connection from harness connector terminal 1 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohms
2. If necessary, repair wire connection.

If voltage supply is OK

Scheme 536

1. Connect multimeter for voltage measurement as follows: HO2S (BEFORE TWC) HEATER CIRCUIT TEST: TERMINAL 2 Harness connector Terminal Measure to 2 B+
2. Operate starter briefly. Specified value: approx. battery voltage
3. Switch ignition off.

If specified value is not obtained

Scheme 537

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1): HO2S (BEFORE TWC) HEATER 1 CIRCUIT TEST: TERMINAL 2 & TEST BOX SOCKET 5 Harness connector Terminal Test box Socket 2 5 Oxygen Sensor (O2S) Heater 2 -Z28- (bank 2, sensor 1): HO2S (BEFORE TWC) HEATER 2 CIRCUIT TEST: TERMINAL 2 & TEST BOX SOCKET 4 Harness connector Terminal Test box Socket 2 4 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

Final procedures

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuse for oxygen sensor heater OK
2. Ground (GND) connections at engine and transmission OK
3. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Ignition switched off.

Note. Voltage for Oxygen Sensor (O2S) Heater 1 (behind Three Way Catalytic Converter (TWC)) -Z29- (bank 1, sensor 2) and Oxygen Sensor (O2S) Heater 2 (behind Three Way Catalytic Converter (TWC)) -Z30- (bank 2, sensor 2) is supplied via the Fuel Pump (FP) relay. Bank 1 = cylinder bank 1 in direction of travel, right; Bank 2 = cylinder bank 2 in direction of travel, left. When servicing terminals in harness connector of Heated Oxygen Sensor (HO2S), use only gold-plated terminals.

1. Disconnect electrical 4-pin harness connector -1- at right from Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29- (bank 1, sensor 2).
2. Disconnect electrical 4-pin harness connector -2- from Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- (bank 2, sensor 2).

1. Connect multimeter between terminal 1 and 2 for resistance measurement. Specified value at room temperature: 2 ... 10 ohm

If specified value is not obtained

1. Replace respective oxygen sensor behind catalytic converter. See «OXYGEN SENSORS BEHIND CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If specified value is obtained

1. Connect multimeter between terminal 1 (B+) and 2 (Ground -GND-) for voltage measurement.
2. Operate starter briefly. Specified value: approx. battery voltage

If there is no voltage

1. Connect multimeter for voltage measurement as follows: HO2S HEATER (BEHIND TWC) CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
2. Operate starter briefly. Specified value: approx. battery voltage
3. Switch ignition off.

If there is no voltage again

1. Check wire connection from harness connector terminal 1 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.

If voltage supply is OK

Scheme 538

1. Connect multimeter for voltage measurement as follows: HO2S HEATER (BEHIND TWC) CIRCUIT TEST: TERMINAL 2 Harness connector Terminal Measure to 2 B+
2. Operate starter briefly. Specified value: approx. battery voltage, possibly fluctuating
3. Switch ignition off.

If specified value is not obtained

Scheme 539

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: Oxygen Sensor (O2S) heater -Z29- bank 1 behind catalytic converter: OXYGEN SENSOR HEATER BANK 1 (BEHIND TWC) CIRCUIT TEST: TERMINAL 2 & TEST BOX SOCKET 63 Harness connector Terminal Test box Socket 2 63 Oxygen Sensor (O2S) heater -Z30- bank 2 behind catalytic converter: OXYGEN SENSOR HEATER BANK 2 (BEHIND TWC) CIRCUIT TEST: TERMINAL 2 & TEST BOX SOCKET 6 Harness connector Terminal Test box Socket 2 6 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuse for Mass Air Flow (MAF) sensor OK
2. Ground (GND) connections at engine and transmission OK
3. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Parking brake engaged.
5. Vehicles with automatic transmission: Selector lever in position "P" or "N".
6. Electrical consumers switched off (radiator fan must NOT run during test).
7. A/C switched off.
8. Coolant temperature at least 80 °C; "PID 05: Coolant temperature". See «MODE 1: CHECK MEASURED VALUES»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-1-check-measured-values) .
9. Ignition switched off.

Note. Voltage is supplied to Mass Air Flow (MAF) sensor from Fuel Pump (FP) relay. Use only gold-plated terminals when servicing terminals in harness connector of Mass Air Flow (MAF) sensor.

Checking function

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measured values."
4. Select the desired measuring value "PID 16: Air flow quantity at Mass Air Flow (MAF) sensor". Specified value: 3,5 ... 7.0 g/s
5. End diagnosis and switch ignition off.

If the specified value is not reached

1. Check intake air system for leaks (false air). See «CHECKING INTAKE SYSTEM FOR LEAKS (UNMETERED AIR)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Check voltage supply and wire connections. See «CHECKING VOLTAGE SUPPLY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If the specified value is exceeded

1. Eliminate engine load via additional equipment (A/C system/power-assisted steering/alternator).
2. Check voltage supply and wire connections. See «CHECKING VOLTAGE SUPPLY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

1. Disconnect harness connector -arrow- at Mass Air Flow (MAF) sensor.
2. Connect multimeter for voltage measurement as follows. MAF SENSOR CIRCUIT TEST: TERMINAL 2 Harness connector Terminal Measure to 2 Engine Ground (GND)
3. Operate starter briefly. Specified value: approx. battery voltage
4. Switch ignition off.

If specified value is not obtained

1. Check wire connection from harness connector terminal 2 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.

If voltage supply is OK

Check Ground (GND) activation

1. Connect multimeter between terminal 2 and 3 of harness connector for voltage measurement.
2. Operate starter briefly. Specified value: approx. battery voltage
3. Switch ignition off.

If specified value is not obtained

1. Check wire connections. See «CHECKING WIRE CONNECTIONS»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__checking-wire-connections) .
2. Connect multimeter between terminal 1 and 3 of harness connector for voltage measurement.
3. Switch ignition on. Specified value: approx. 5 V
4. Switch ignition off.

If specified value is not obtained

Checking wire connections

Note. Signal wire is also checked during wire test.

Scheme 540

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: MAF SENSOR CIRCUIT TEST: TERMINAL 3, 4, 5 & TEST BOX SOCKET 27, 53, 29 Harness connector Terminal Test box Socket 3 27 4 53 5 (signal wire) 29 Specified value: Wire resistance max 1.5 ohms
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Mass Air Flow (MAF) sensor -G70-. See item 5 .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

Throttle valve control module -J338-, checking

The following components are located in the housing for the throttle valve control module

1. Throttle drive (power accelerator actuation) -G186-. (This is an electric motor that is activated by the ECM. This electric motor opens the throttle valve against spring pressure.)
2. Angle sensor -1- for throttle drive (power accelerator actuation) -G187
3. Angle sensor -2- for throttle drive (power accelerator actuation) -G188

Note. The housing for the throttle valve control module must not be opened. The angle sensors are designed as potentiometers (variable resistances). They communicate the position of the throttle valve to the Engine Control Module (ECM) fully independent of each other.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Ground (GND) connections at engine and transmission OK
3. Battery voltage at least 12.7 V
4. Parking brake engaged.
5. Vehicles with automatic transmission: Selector lever in position "P" or "N".
6. Electrical consumers switched off (radiator fan must NOT run during test).
7. A/C switched off.
8. Coolant temperature at least 80 °C; "PID 05: Coolant temperature". See «MODE 1: CHECK MEASURED VALUES»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-1-check-measured-values) .

Note. Use only gold-plated terminals when servicing terminals in harness connector of throttle valve control module.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Switch ignition on.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measured values."
4. Select the desired measuring value "PID 17: Throttle valve position (absolute)." Specified value: 10 to 20 %
5. Slowly depress accelerator pedal completely. Specified value: The percentage display must increase uniformly
6. Hold accelerator pedal fully depressed; in vehicles with automatic transmission, do not depress beyond the kickdown point when doing this. Specified value: 80 to 90 %
7. Switch ignition off.

If specified values are not obtained

1. Check voltage supply and wire connections of throttle valve control module. See «CHECKING VOLTAGE SUPPLY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) . Pay particular attention to harness connectors that could be loose or corroded.
2. Check Throttle Position (TP) sensor. See «THROTTLE POSITION (TP) SENSOR, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
3. Disconnect electrical harness connector (arrow) at Throttle Valve Control Module -J338-.

Scheme 541

1. Switch ignition on.
2. Connect multimeter for voltage measurement as follows: THROTTLE VALVE CONTROL MODULE CIRCUIT TEST: TERMINALS 2 & 6 Harness connector Terminal Specified value 2 + Ground (GND) approx. 5 V 2 + 6 approx. 5 V
3. Switch ignition off.

If specified values are not obtained

Scheme 542

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: THROTTLE VALVE CONTROL MODULE CIRCUIT TEST: TERMINAL & TEST BOX SOCKET REFERENCE Harness connector Terminal Test box Socket 1 92 2 83 3 117 4 84 5 118 6 91 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunction is detected in the wiring and if the voltage supply was OK

1. Replace Throttle Valve Control Module -J338-.
2. After replacing the throttle valve control module, it must be adapted. For this purpose switch on ignition for at least 30 seconds without starting engine or depressing accelerator pedal.
3. Switch ignition off. Engine Control Module (ECM) now requires approx. 3 seconds to store the learned value. At this time, the ignition must not be switched on again

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

Note. The engine speed (RPM) sensor detects RPM and reference marks. The engine cannot be started without a signal from the engine speed (RPM) sensor -G28-. If the engine speed (RPM) sensor -G28- signal fails while the engine is running, the engine will stop immediately.

Test requirement

1. Ignition switched off.

1. Before performing test, check sensor for proper installation and proper fitting.
2. No shavings or damage at Engine Speed (RPM) Sensor or sensor wheel.
3. Thickness of the spacer disc between sensor and automatic transmission must be 4.5 mm.
4. Disconnect electrical harness connector from Engine Speed (RPM) sensor. See item 13 .

1. Connect multimeter between terminal 2 and 3 for resistance measurement. Specified value: 450 to 1000 ohms

Note. Resistance value of the engine speed (RPM) sensor is based on a temperature of 20 °C. Resistance increases as temperature increases.

If specified value is not obtained

1. Replace engine speed (RPM) sensor.

If specified value is obtained

1. Connect multimeter to terminals 2 and 1 (shielding) and to terminals 3 and 1 (shielding) for resistance measurement. Specified value: each INFINITY ohm (no continuity)

If specified value is not obtained

1. Replace engine speed (RPM) sensor.

If specified value is obtained

Scheme 543

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: ENGINE SPEED (RPM) SENSOR CIRCUIT TEST: TERMINAL 1, 2, 3 & TEST BOX SOCKET 108, 90, 82 Harness connector Terminal Test box Socket 1 (shielding) 108 2 (Ground -GND-) 90 3 (signal) 82 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires.

1. Slowly rotate engine and check sensor wheel for run-out and secure seating.

If no malfunctions are detected

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

Intake Air Temperature (IAT) sensor -G42-, checking

Note. Intake Air Temperature (IAT) Sensor -G42- is integrated in Mass Air Flow (MAF) Sensor -G70-.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Ignition switched off.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measured values."
4. Select the desired measuring value "PID 15: Intake air temperature". Specified value: approx. ambient temperature NOTE: If a temperature is indicated which differs greatly from ambient temperature of sensor, check sensor and sensor wires for contact resistances and open circuit.
5. End diagnosis and switch ignition off.

If indications do not resemble description

Scheme 544

1. Disconnect harness connector -arrow- at Mass Air Flow (MAF) sensor.
2. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
3. Check the following wire connection for open circuit according to wiring diagram: IAT SENSOR CIRCUIT TEST: TERMINAL 1, 3 & TEST BOX SOCKET 85, 27 Harness connector Terminal Test box Socket 1 85 3 27 Specified value: Wire resistance max 1.5 ohm
4. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
5. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Mass Air Flow (MAF) sensor -G70-.

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

Engine Coolant Temperature (ECT) sensor -G62-, checking

Component location. See OVERVIEW OF COMPONENT LOCATIONS .

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Engine cold

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Switch ignition on.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measured values."
4. Select the desired measuring value "PID 05: Coolant temperature". Specified value: approx. ambient temperature NOTE: If a temperature is indicated which differs greatly from ambient temperature of sensor, check sensor and sensor wires for contact resistances and open circuit.
5. Start engine and let run at idle. Specified value: Temperature value must rise evenly NOTE: The temperature increases in increments of 1.0 °C. If the engine shows problems in certain temperature ranges and if the temperature does not climb uniformly, the temperature signal is intermittent and the sensor should be replaced.
6. End diagnosis and switch ignition off.

If indications do not resemble description

Scheme 545

1. Disconnect harness connector -4- at Engine Coolant Temperature (ECT) Sensor -G2-/-G62-. NOTE: Disregard the other items.
2. Connect multimeter between terminal C and D of sensor for resistance measurement. Range A displays resistance values for the temperature range of 0 to 50°C, range B displays resistance values for the temperature range of 50 to 100 °C.

Read-out examples

1. 30 °C corresponds to a resistance of 1500 to 2000 ohm
2. 80 °C corresponds to a resistance of 275 to 375 ohm

If specified value is not obtained

1. Replace Engine Coolant Temperature (ECT) sensor (G62).

If specified value is obtained

Scheme 546

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: ECT SENSOR CIRCUIT TEST: TERMINAL 3, 4 & TEST BOX SOCKET 108, 93 Harness connector Terminal Test box Socket 3 108 4 (signal) 93 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. V.A.G 1527 B Voltage Tester
3. VAG1594A connector test kit
4. VAG1598/31 test box

1. Fuse for solenoid valves for camshaft adjustment OK.
2. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
3. Motronic Engine Control Module (ECM) Power Supply Relay -J271- OK; checking. See «CHECK MOTRONIC ENGINE CONTROL MODULE (ECM) POWER SUPPLY RELAY -J271- AND ACTIVATION»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Ignition switched off.

Note. In vehicles without Motronic Engine Control Module (ECM) Power Supply Relay -J271-, voltage is supplied to camshaft adjustment solenoid valves via the Fuel Pump (FP) relay. In vehicles with Motronic Engine Control Module (ECM) Power Supply Relay -J271-, voltage is supplied to camshaft adjustment solenoid valves via -J271-.

Cylinder bank 1 (right)

1. Remove air guide hose -1- between Mass Air Flow (MAF) sensor and throttle valve control module (arrows).
2. Disconnect electrical harness connector from Valve -1- for camshaft adjustment (-2-).

Cylinder bank 2 (left)

1. Remove engine cover (arrows).
2. Disconnect electrical harness connector (arrow) from Valve -2- for camshaft adjustment -N208-.

1. Connect multimeter at valve for resistance measurement. Specified value: 10 to 18 ohms

If specified value is not obtained

1. Replace the respective solenoid valve for camshaft adjustment. See «CAMSHAFTS AND CAMSHAFT ADJUSTERS, REMOVING AND INSTALLING»(ref-196260-S04268046642005100700000) for ART, AWN, BBD.

If specified value is obtained

Scheme 547

1. Connect e.g. V.A.G 1527 B voltage tester as follows: CAMSHAFT ADJUSTMENT VALVE CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
2. Switch ignition on. LED must light up.
3. Switch ignition off.

If LED does not light up

1. Check wire connection from terminal 1 of harness connector via fuse to Fuel Pump (FP) Relay -J17- or Motronic Engine Control Module (ECM) Power Supply Relay -J271- (depending on version) for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.

If voltage supply is OK

Scheme 548

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: Valve -1- for camshaft adjustment -N205- (bank 1): CAMSHAFT ADJUSTMENT VALVE CIRCUIT TEST: BANK 1 TERMINAL 2 & TEST BOX SOCKET 115 Harness connector Terminal Test box Socket 2 115 Valve -2- for camshaft adjustment -N208- (bank 2): CAMSHAFT ADJUSTMENT VALVE CIRCUIT TEST: BANK 2 TERMINAL 2 & TEST BOX SOCKET 120 Harness connector Terminal Test box Socket 2 120 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

If no malfunctions are detected

1. Replace mechanical camshaft adjuster. See «CAMSHAFTS AND CAMSHAFT ADJUSTERS, REMOVING AND INSTALLING»(ref-196260-S04268046642005100700000) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

Voltage is supplied to the Fuel Pump (FP) and several components of the injection system via the Fuel Pump (FP) Relay -J17-.

Engine must be turning for Fuel Pump (FP) Relay -J17- to close. This means that the relay does not receive Ground (GND) (via ECM) until the ECM recognizes RPM signals.

1. Battery voltage at least 12.7 V
2. Ignition switched off.

Scheme 549

1. Remove driver-side storage compartment: See «DRIVER'S STORAGE COMPARTMENT, REMOVING»(/audi/s6/c5-1999-2004/remont/mirrors/#interior-equipment__drivers-storage-compartment-removing) .
2. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
3. Bridge terminals 1 and 65 at test box using wires e.g. from V.A.G 1594 A adapter test kit.
4. Switch ignition on. Fuel Pump (FP) relay (at position 4 of central electronics in driver's footwell, left) must trigger and Fuel Pump (FP) must run.

A - If Fuel Pump (FP) runs

1. Check voltage supply of Fuel Pump (FP) relay. See «CHECK VOLTAGE SUPPLY OF FUEL PUMP (FP) RELAY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Checking activation of Fuel Pump (FP) relay. See «CHECKING ACTIVATION OF FUEL PUMP (FP) RELAY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

B - If Fuel Pump (FP) does not run

1. Check voltage supply for Fuel Pump (FP) and components (via Fuel Pump -FP- relay). See «CHECK VOLTAGE SUPPLY FOR FUEL PUMP (FP) AND COMPONENTS»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__check-voltage-supply-for-fuel-pump) .

Scheme 550

1. Remove Fuel Pump (FP) relay.
2. Connect multimeter for voltage measurement as follows. FUEL PUMP RELAY CIRCUIT TEST: TERMINAL 17 Central electronics in driver-side footwell, left, position 4 Terminal Measure to 17 Chassis Ground (GND) Specified value: approx. battery voltage

If specified value is not obtained

1. Replace central electronics.
2. Connect multimeter for voltage measurement as follows: FUEL PUMP RELAY CIRCUIT TEST:TERMINAL 19 Central electronics in driver-side footwell, left, position 4 Terminal Measure to 19 Engine Ground (GND)
3. Switch ignition on. Specified value: approx. battery voltage
4. Switch ignition off.

If specified value is not obtained

1. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm

If specified values are obtained

Scheme 551

1. Remove cable bridge.
2. Remove Fuel Pump (FP) relay.
3. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
4. Check the following wire connection for open circuit according to wiring diagram: FUEL PUMP RELAY CIRCUIT TEST: TERMINAL 16 & TEST BOX SOCKET 65 Central electronics in driver-side footwell, left, position 4 Terminal Test box Socket 16 65 Specified value: Wire resistance max 1.5 ohm
5. Also check the wire for short circuit to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
6. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Fuel Pump (FP) Relay -J17-.
2. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

Check voltage supply for Fuel Pump (FP) and components

1. Remove fuses S228, S232, and S234 (positions 28, 32, and 34) from fuse holder.
2. Connect multimeter for voltage measurement to Ground (GND) and to one terminal of the following fuses in the fuse holder.
3. Operate starter briefly. FUEL PUMP RELAY FUSE SPECIFICATIONS Fuse Specified value at one of the terminals S228 approx. battery voltage S232 approx. battery voltage S234 approx. battery voltage

If specified values are not obtained

1. Repeat test at another terminal of fuse socket.

If specified values are not obtained again

1. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm

If no malfunctions are detected

1. Replace Fuel Pump (FP) Relay -J17-.
2. Re-insert the fuses.

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. Fuel Inj. Pressure Gauge Set V.A.G 1318 with adapters V.A.G 1318/6 and V.A.G 1318/7

1. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Delivery quantity of Fuel Pump (FP) OK; check. See «DELIVERY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
3. Fuel filter OK
4. Parking brake engaged.
5. Vehicles with automatic transmission: Selector lever in P or N.
6. Electrical consumers switched off (radiator fan must NOT run during test).
7. A/C switched off.
8. Ignition switched off.

1. Remove engine cover (arrows).

Scheme 552

1. Open fuel filler flap briefly (pressure release). CAUTION: Fuel system is under pressure! Before opening system, place rags around the connection area. Then release pressure by carefully loosening connection.
2. Open screw connection (arrow).
3. Connect e.g. V.A.G 1318 pressure gauge to fuel supply line using adapters 1318/6 and 1318/7.
4. Disconnect vacuum line (arrow) from fuel pressure regulator to intake manifold at fuel pressure regulator and seal line. NOTE: If fuel should escape at the vacuum connection of the pressure regulator during the following pressure test, replace pressure regulator.
5. Start engine and let run at idle.
6. Measure fuel pressure. Specified value: approx. 4.0 bar
7. Switch ignition off.

If specified value is not obtained

1. Replace fuel pressure regulator as a test and repeat pressure test.

If specified value is again not obtained

1. Check Fuel Pump (FP) and supply line for damage (e.g. pinched areas), replace if necessary.

If the specified value is exceeded again

1. Check fuel return line for damage (e.g. pinched areas), replace if necessary. NOTE: During the following test, the engine must not run for an unnecessarily long period of time with the vacuum hose removed. Otherwise, the higher fuel pressure can cause enrichment of the fuel to air ratio, which under some circumstances can cause the oxygen sensor control limits to be exceeded, causing a DTC to be stored.
2. Start engine and let run at idle.
3. Connect vacuum hose at fuel pressure regulator while observing pressure drop at pressure gauge.
4. Fuel pressure must drop by approx. 0.5 bar when connecting the vacuum hose. If the pressure change does not occur, the following tests must be performed: Check vacuum hose for tears and damage. Check vacuum hose at intake manifold for throughput by disconnecting hose from fuel pressure regulator and blowing into it.
5. If no leaks can be detected and if the vacuum hose has throughput, replace the fuel pressure regulator.

Checking residual pressure

1. Residual pressure 10 minutes after switching engine off (minimum pressure). Specified value: approx. 2.5 bar
2. Start engine and let run at idle.
3. Wait until pressure has risen, and then switch off ignition. Simultaneously close shut-off valve of VAG1318 pressure gauge (lever perpendicular to direction of flow -arrow-).
4. Observe pressure drop on pressure gauge.
5. Switch ignition off.

The following malfunctions are possible if the pressure does not drop

1. There is a leak in the screw connection between the pressure gauge and the fuel supply line
2. There is a leak at the supply line at fuel tank.
3. There is a leak in the check valve in the Fuel Pump (FP). See «DELIVERY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Note. After the shut-off valve is closed, pressure gauge displays the pressure behind the shut-off valve "intake manifold side" (in direction of fuel injectors, fuel pressure regulator). If the pressure drops in front of the shut-off valve (in direction of fuel tank), the device cannot detect it.

The following malfunctions are possible if the pressure drops again

1. Fuel pressure regulator faulty
2. Fuel injectors not properly sealed
3. Screw connections of pressure gauge behind shut-off valve are not properly sealed.

Note. To remove pressure gauge, close shut-off valve, loosen screw connection at VAG1318/7 adapter and let excess fuel escape into catch reservoir by opening shut-off valve.

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. V.A.G 1527 B Voltage Tester
3. VAG1594A connector test kit
4. VAG1598/31 test box

1. Fuse for fuel injectors OK
2. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
3. Ignition switched off.

Note. Voltage is supplied to the fuel injectors via the Fuel Pump (FP) relay.

1. Remove engine cover (arrows).
2. Disconnect all harness connectors (arrows) at fuel injectors of the relevant cylinder bank. NOTE: Disregard items -1- and -2-.

1. Connect multimeter at valve for resistance measurement. Specified value: 13 to 16 ohm (at room temperature)

With an engine at operating temperature, the resistance increases by approx. 4 to 6 ohm.

If specified value is not obtained

1. Replace fuel injector. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__fuel-injectors-removing-and-installing) .

If specified value is obtained

Scheme 553

1. Connect e.g. V.A.G 1527 B voltage tester as follows: FUEL INJECTOR CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
2. Switch ignition on. LED must light up.
3. Switch ignition off.

If LED does not light up

1. Check wire connection from harness connector terminal 1 to Fuel Pump (FP) Relay -J17- via fuse for open circuit according to wiring diagram. Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.

If LED lights up

1. Internal resistance of valve OK

1. Connect voltage tester e.g. V.A.G 1527 B with measuring probes and connector adapters from V.A.G 1594 A between terminal 2 (signal) and terminal 1 (B+); the harness connector remains connected.
2. Operate starter briefly (engine can also start). LED must blink. NOTE: Voltage testers do not go out completely during low current pick-up between activations by the ECM, but rather continue to glow a little and then get slightly brighter during activation.
3. Switch ignition off.

If LED does not blink

Scheme 554

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: FUEL INJECTOR CIRCUIT TEST: TERMINAL 2 CYLINDERS & TEST BOX SOCKETS Cylinder Fuel injector harness connector Terminal Test box Socket 1 2 96 2 2 23 3 2 113 4 2 88 5 2 97 6 2 112 7 2 24 8 2 89 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1348/3A remote control with VAG1348/3-2 adapter cable
2. VAG1594A connector test kit
3. VAG1598/31 test box
4. V.A.G 1602 tester for quantity of injected fuel

1. Fuel pressure OK, checking. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Ignition switched off.

Test sequence

1. Remove fuel rail including fuel injectors from intake manifold. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__fuel-injectors-removing-and-installing) . Fuel lines remain connected.
2. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.

Checking Proper Seal

1. Bridge terminals 1 and 65 at test box using wires e.g. from V.A.G 1594 A adapter test kit.
2. Switch ignition on. Fuel Pump (FP) must run.
3. Check proper seal of fuel injectors (visual inspection). With Fuel Pump (FP) running, only 1 to 2 drops per minute may drip out per injector.
4. If fuel loss is greater, stop Fuel Pump (FP) from running (switch off ignition) and replace faulty fuel injector. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__fuel-injectors-removing-and-installing) .

Checking Injection Quantity

1. Insert fuel injector to be tested in a measuring glass from e.g. V.A.G 1602 injection quantity test device.
2. Connect one terminal of fuel injector to engine Ground (GND) using an adapter cable and an alligator clip e.g. from VAG1594A connector test kit.
3. Connect the second terminal of fuel injector to B+ using e.g. VAG1348/3A remote control, VAG1348/3-2 adapter cable and assisting cable.
4. Bridge terminals 1 and 65 at test box using wires e.g. from V.A.G 1594 A adapter test kit.
5. Switch ignition on. Fuel Pump (FP) must run.
6. Operate remote control for 30 seconds.
7. After all three fuel injectors of one cylinder row have been activated, place measuring glasses on an even surface.

Specified value for each fuel injector

FUEL INJECTOR INJECTION QUANTITY SPECIFICATIONS

1. If measured value of one or more fuel injectors is outside of specified range, switch Fuel Pump (FP) off (switch ignition off) and replace faulty fuel injector. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__fuel-injectors-removing-and-installing) .
2. Repeat test at fuel injectors of second cylinder row.
3. If the measured values of all fuel injectors are outside the specified range, check fuel pressure. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) . NOTE: Also check spray pattern when checking injection quantity. Spray pattern must be the same for all injectors
4. Install fuel injectors together with fuel rail. See «INSTALLING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__installing) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. Engine leak detection spray G 001 800 A1

Note. The negative pressure in the intake system sucks in the leak detection spray with the unmetered air. Leak detection spray decreases ignition quality of the fuel mixture. This causes a reduction in engine speed and a sharp increase of CO content. It is absolutely necessary to follow the safety precautions listed on the can.

1. Coolant temperature at least 80 °C; "PID 05: Coolant temperature". See «MODE 1: CHECK MEASURED VALUES»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-1-check-measured-values) .
2. Ignition switched off.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measured values." NOTE: Bank 1 = cylinder bank 1 in direction of travel, right; Bank 2 = cylinder bank 2 in direction of travel, left.
4. Select the following measured values: PID SPECIFIED VALUES PID Diagnostic text Specified value 06: Short time gasoline-air ratio bank 1 -7.00...7.00 % 08: Short time gasoline-air ratio bank 2 -7.00...7.00 % 12: Engine rotations per minute (RPM) Audi A6: 670 to 730 RPM Audi S6: 740 to 820 RPM
5. Spray intake system parts with engine leak detection spray in a systematic manner.

If engine speed drops or if the short-term gasoline-air ratio changes

1. End diagnosis and switch ignition off.
2. Check sprayed part of intake system for leaks, and repair the malfunction.

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Ground (GND) connections at engine and transmission OK
3. Oxygen sensor heater OK; check «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEFORE THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Exhaust system free of leaks.
5. Parking brake engaged.
6. Vehicles with automatic transmission: Selector lever in position "P" or "N".
7. Electrical consumers switched off (radiator fan must NOT run during test).
8. A/C switched off.
9. Coolant temperature at least 80 °C; "PID 05: Coolant temperature". See «MODE 1: CHECK MEASURED VALUES»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-1-check-measured-values) .

Note. Bank 1 = cylinder bank 1 in direction of travel, right; Bank 2 = cylinder bank 2 in direction of travel, left. When selecting the diagnostic mode, the entry is always performed in "Bank 1 sensor 1". If either the VAG1551/1552 Scan Tool (ST) or VAS5051/5052 Vehicle Diagnostic, Testing and Information System is used for checking the output of oxygen sensor signals, the respective oxygen sensor can be selected by pressing button 1, 2, 5 and 6: - Button 1 = Bank 1 sensor 1, - Button 2 = Bank 1 sensor 2, - Button 5 = Bank 2 sensor 1, - Button 6 = Bank 2 sensor 2. When servicing terminals in harness connector of Heated Oxygen Sensor (HO2S), use only gold-plated terminals.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 5: Check output of oxygen sensor signals".
4. Select the desired output of oxygen sensor signals according to the following table. MODE 5: CHECK OUTPUT OF OXYGEN SENSOR SIGNALS Test-ID Diagnostic text Specified value: min. max. 07: Minimum voltage at sensor for test cycle Bank 1 sensor 1 0.000 V 0.385 V Minimum voltage at sensor for test cycle Bank 2 sensor 1 0.000 V 0.385 V 08: Maximum voltage at sensor for test cycle Bank 1 sensor 1 0.480 V 1.005 V Maximum voltage at sensor for test cycle Bank 2 sensor 1 0.480 V 1.005 V 09: Time period between sensor shift procedures (half value) Bank 1 sensor 1 0.040/s 0.920/s Time period between sensor shift procedures (half value) Bank 2 sensor 1 0.120/s 0.920/s
5. Check values of output for oxygen sensor signals.

If specified values are not obtained

1. Road test vehicle in order to free oxygen sensors of possible residue and repeat test.

If specified values are not obtained again

1. Check primary voltage. See «CHECKING PRIMARY VOLTAGE»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__checking-primary-voltage) .
2. Test oxygen sensor heater before catalytic converter. See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEFORE THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
3. Check intake system for leaks (false air). See «CHECKING INTAKE SYSTEM FOR LEAKS (UNMETERED AIR)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC). See «OXYGEN SENSORS AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__oxygen-sensors-and-oxygen-sensor-control) .
5. Check fuel pressure regulator and residual pressure. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
6. Check fuel injectors. See «FUEL INJECTORS, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
7. Check Evaporative Emission (EVAP) canister purge regulator valve -N80-. See «CHECKING EVAPORATIVE EMISSION (EVAP) CANISTER PURGE REGULATOR VALVE -N80»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
8. Check Fuel Pump (FP). See «FUEL PUMP (FP), ELECTRICAL TESTING»(/audi/s6/c5-1999-2004/remont/fuel-system/#fuel-supply-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
9. Check exhaust system for proper seal. See «EXHAUST SYSTEM, CHECKING FOR PROPER SEAL»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__exhaust-system-checking-for-proper-seal) .
10. Check Secondary Air Injection (AIR) system for proper seal. See «CHECKING SECONDARY AIR SYSTEM FOR PROPER SEAL»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd__checking-secondary-air-system-for-proper) .
11. Check vacuum lines for proper seal.

Checking primary voltage

1. Disconnect electrical 4-pin harness connector -3- from Heated Oxygen Sensor (HO2S) -G39- (before catalytic converter) and Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1).
2. Disconnect electrical 4-pin harness connector (arrow) from Heated Oxygen Sensor (HO2S) 2 -G108- (before catalytic converter) and Oxygen Sensor (O2S) 2 Heater 2 -Z28- (bank 2, sensor 1).
3. Connect multimeter between terminal 3 and 4 for voltage measurement.
4. Switch ignition on. Specified value: 0,400 ... 0.500 V
5. Switch ignition off.

If specified value is not obtained

1. Check oxygen sensor wires. Bank 1 see «CHECK OXYGEN SENSOR WIRES FOR HEATED OXYGEN SENSOR (HO2S) -G39- (BANK 1, SENSOR 1)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) and Bank 2 see «CHECK OXYGEN SENSOR WIRES FOR HEATED OXYGEN SENSOR (HO2S) 2 -G108- (BANK 2, SENSOR 1)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If specified value is obtained

1. Replace respective oxygen sensor before catalytic converter. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Scheme 555

1. Connect V.A.G 1598/31 test box at wiring harness to Engine Control Module (ECM), do not connect ECM. See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Check the following wire connections for open circuit according to wiring diagram: HO2S -G39- CIRCUIT TEST: TERMINAL 3, 4 & TEST BOX SOCKET 51, 70 Harness connector Terminal Test box Socket 3 51 4 70 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

Scheme 556

1. Connect V.A.G 1598/31 test box at wiring harness to Engine Control Module (ECM), do not connect ECM. See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Check the following wire connections for open circuit. HO2S -G108- CIRCUIT TEST: TERMINAL 3, 4 & TEST BOX SOCKET 12, 13 Harness connector Terminal Test box Socket 3 12 4 13 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) . End diagnosis and switch ignition off.

Oxygen sensors and oxygen sensor control behind catalytic converter, checking

Note. The oxygen sensor before catalytic converter (bank 1, sensor 1 or bank 2, sensor 1) regulates to Lambda 1. If this oxygen sensor is damaged, e.g. due to soiling or overheating, the regulation value may have shifted. Deviations from Lambda 1 are detected by the oxygen sensor behind catalytic converter (bank 1, sensor 2 or bank 2, sensor 2). If it recognizes the deviations downward or upward, it influences the regulation before catalytic converter, generally increasing or decreasing it respectively.

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Ground (GND) connections at engine and transmission OK
3. Oxygen sensor heater OK; check. See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEFORE THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
4. Exhaust system free of leaks.
5. Parking brake engaged.
6. Vehicles with automatic transmission: Selector lever in position "P" or "N".
7. Electrical consumers switched off (radiator fan must NOT run during test).
8. A/C switched off.
9. Coolant temperature at least 80 °C; "PID 05: Coolant temperature". See «MODE 1: CHECK MEASURED VALUES»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-1-check-measured-values) .

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 5: Check output of oxygen sensor signals". NOTE: Bank 1 = cylinder bank 1 in direction of travel, right; Bank 2 = cylinder bank 2 in direction of travel, left. When selecting the diagnostic mode, the entry is always performed in "Bank 1 sensor 1". If either the VAG1551/1552 Scan Tool (ST) or VAS5051/5052 Vehicle Diagnostic, Testing and Information System is used for checking the output of oxygen sensor signals, the respective oxygen sensor can be selected by pressing button 1, 2, 5 and 6: - Button 1 = Bank 1 sensor 1, - Button 2 = Bank 1 sensor 2, - Button 5 = Bank 2 sensor 1, - Button 6 = Bank 2 sensor 2.
4. Select the desired output of oxygen sensor signals according to the following table. MODE 5: CHECK OUTPUT OF OXYGEN SENSOR SIGNALS Test-ID Diagnostic text Specified value: min. max. 07: Minimum voltage at sensor for test cycle Bank 1 sensor 2 0.000 V 0.600 V Minimum voltage at sensor for test cycle Bank 2 sensor 2 0.000 V 0.600 V 08: Maximum voltage at sensor for test cycle Bank 1 sensor 2 0.600 V 1.005 V Maximum voltage at sensor for test cycle Bank 2 sensor 2 0.600 V 1.005 V
5. Check values of output for oxygen sensor signals.

*) V = Voltage in Volts (oxygen sensor signal)

**) t = Time in seconds

If specified values are not obtained

1. Road test vehicle in order to free oxygen sensors of possible residue and repeat test.

If specified values are not obtained again

1. Disconnect electrical 4-pin harness connector -1- from Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 (behind Three Way Catalytic Converter (TWC)) -Z29- (bank 1, sensor 2).
2. Disconnect electrical 4-pin harness connector -2- from Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- (bank 2, sensor 2).
3. Connect multimeter between terminal 3 and 4 for voltage measurement.
4. Switch ignition on. Specified value: 0.400 to 0.500 V
5. Switch ignition off.

If specified value is not obtained

1. Check oxygen sensor wires Bank 1. See «CHECK OXYGEN SENSOR WIRES FOR OXYGEN SENSOR (O2S) BEHIND THREE WAY CATALYTIC CONVERTER (TWC) -G130- (BANK 1, SENSOR 2)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) and for Bank 2 see «CHECK OXYGEN SENSOR WIRES FOR OXYGEN SENSOR (O2S) BEHIND THREE WAY CATALYTIC CONVERTER (TWC) -G131- (BANK 2, SENSOR 2)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

If specified value is obtained

1. Replace respective oxygen sensor behind catalytic converter. See «OXYGEN SENSORS BEHIND CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/s6/c5-1999-2004/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Scheme 557

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HO2S -G130- CIRCUIT TEST: TERMINAL 3, 4 & TEST BOX SOCKET 68, 69 Harness connector Terminal Test box Socket 3 68 4 69 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

Scheme 558

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HO2S -G131-: TERMINAL 3, 4 & TEST BOX SOCKET 10, 11 Harness connector Terminal Test box Socket 3 10 4 11 Specified value: Wire resistance max 1.5 ohm
3. Also check wires for short circuit to each other as well as to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Replace Engine Control Module (ECM). See «REPLACING ENGINE CONTROL MODULE (ECM)»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__replacing-engine-control-module-ecm) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK
2. Ground (GND) connections at engine and transmission OK
3. Battery voltage at least 12.7 V
4. Generator OK
5. Ignition switched off.

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Switch ignition on. NOTE: The plus voltage supply for the Engine Control Module (ECM) travels via contact 3 (terminal 15) and contact 62 (terminal 30). Ground (GND) supply of the Engine Control Module (ECM) travels via terminal 1 and terminal 2.
3. Connect multimeter for voltage measurement as follows: ECM CIRCUIT TEST: TEST BOX SOCKET 1, 2 & 62 Test box Socket Measure to 1 B+ 2 B+ 62 Engine Ground (GND) Specified value: approx. battery voltage
4. Switch ignition off.
5. Connect multimeter for voltage measurement as follows: ECM CIRCUIT TEST: TEST BOX SOCKET 3 Test box Socket Measure to 3 Engine Ground (GND)
6. Switch ignition on. Specified value: approx. battery voltage
7. Switch ignition off.

If specified values are not obtained

1. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.
3. Check Motronic Engine Control Module (ECM) voltage supply relay -J271-. See «CHECK MOTRONIC ENGINE CONTROL MODULE (ECM) POWER SUPPLY RELAY -J271- AND ACTIVATION»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Special Tools and Equipment

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

Note. Motronic Engine Control Module (ECM) Power Supply Relay -J271- is not installed on all versions.

1. Ignition switched off.

Scheme 559

Scheme 560

1. Remove engine cover (arrows).
2. Remove cover -2- above the cylinder head cover, left.
3. Disconnect one of the 4-pin harness connectors -4- at ignition coils. NOTE: For further testing, connect the multimeter to harness connector in place of an ignition coil.
4. Connect multimeter for voltage measurement as follows. ECM POWER SUPPLY RELAY CIRCUIT TEST: TERMINAL 1 Harness connector Terminal Measure to 1 Engine Ground (GND)
5. Switch ignition on. Specified value: approx. battery voltage
6. Switch ignition off.

If specified value is not obtained

Scheme 561

Scheme 562

1. Pull off rubber seal of plenum chamber cover in direction of arrow.
2. Remove plenum chamber cover -1- toward front.
3. Remove cover for E-box, plenum chamber (arrows).
4. Pry off Engine Control Module (ECM) retaining bracket (arrow) using a screwdriver and set control module aside.
5. Remove voltage supply relay -3-.
6. Check the following wire connection for open circuit according to wiring diagram: ECM POWER SUPPLY RELAY CIRCUIT TEST: TERMINALS 8 & 1 Relay carrier in E-box, plenum chamber, position 3 Terminal Harness connector at ignition coils Terminal 8 1 Specified value: Wire resistance max 1.5 ohm
7. If necessary, repair wire connection.

If no malfunctions are found in wires

1. Check voltage supply of Motronic Engine Control Module (ECM) voltage supply relay -J271-. See «CHECKING VOLTAGE SUPPLY»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Check activation of Motronic Engine Control Module (ECM) voltage supply relay -J271-. See «CHECKING ACTIVATION»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Scheme 563

1. Connect multimeter for voltage measurement as follows. ECM POWER SUPPLY RELAY CIRCUIT TEST: TERMINAL 1 & 2 Relay carrier in E-box, plenum chamber, position 3 Terminal Measure to 1 Engine Ground (GND) 2 Engine Ground (GND) Specified value: approx. battery voltage

If specified value is not obtained

1. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm

Scheme 564

1. Connect multimeter for voltage measurement as follows. ECM POWER SUPPLY RELAY CIRCUIT TEST: TERMINAL 4 Relay carrier in E-box, plenum chamber, position 3 Terminal Measure to 4 B+
2. Switch ignition on. Specified value: approx. battery voltage
3. Switch ignition off.

If specified value is not obtained

Scheme 565

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; ECM is not connected.
2. Check the following wire connection for open circuit according to wiring diagram: ECM POWER SUPPLY RELAY CIRCUIT TEST: TERMINAL 4 & TEST BOX SOCKET 23 Relay carrier in E-box, plenum chamber, position 3 Terminal Test box Socket 4 23 Specified value: Wire resistance max 1.5 ohm
3. Also check the wire for short circuit to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
4. If necessary, repair wire connection.

If no malfunctions are detected

1. Replace Motronic Engine Control Module (ECM) voltage supply relay -J271-.

Removing

1. Switch ignition off.
2. Pull off rubber seal of plenum chamber cover in direction of arrow.
3. Remove plenum chamber cover -1- toward front.
4. Remove cover for E-box, plenum chamber (arrows).
5. Using a screwdriver, carefully pry off retaining bracket (arrow).
6. Disengage connector catches (arrows) and disconnect harness connectors -1- and -2- from Engine Control Module (ECM). NOTE: Adaptation values are erased when connector is disconnected from the Engine Control Module (ECM), DTC memory content remains intact.
7. Remove Engine Control Module (ECM).

Installation is performed in the reverse order of removal.

After connecting harness connectors to Engine Control Module (ECM), the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. If DTC memory was erased, generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Replacing Engine Control Module (ECM)

Note. To achieve optimal anti-theft protection for the vehicle, an anti-theft immobilizer was installed. The anti-theft immobilizer is a system for enabling/locking the Engine Control Module (ECM). So that this system cannot be circumvented, it is necessary to perform adaptation of the anti-theft immobilizer using the VAS 5052 in the On Board Diagnostic (OBD) function. The great availability of equipment options makes adaptation of the Engine Control Module (ECM) necessary (e.g. cruise control system). This "writing" function is not possible with the generic scan tool, therefore it is necessary to use the VAS 5052 in On Board Diagnostic (OBD) function for this purpose. Procedure to replace Engine Control Module (ECM): For engine codes ART and AWN, see MOTRONIC ENGINE CONTROL MODULE (ECM) -J220 (WITHOUT METAL ANTI -THEFT HOUSING), REPLACING or MOTRONIC ENGINE CONTROL MODULE (ECM) -J220 (WITH METAL ANTI -THEFT HOUSING), REPLACING . For engine code BBD, see MOTRONIC ENGINE CONTROL MODULE (ECM) -J220-, REPLACING .

After connecting harness connectors to Engine Control Module (ECM), the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. If DTC memory was erased, generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

1. Function and display of speedometer OK. Troubleshooting

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Diagnostic mode 1 - Check measuring values".
4. Select the desired measuring value "PID 13: Vehicle speed".
5. Perform a road test, and have a 2nd person observe the indication on the display. PID 13: VEHICLE SPEED PID Diagnostic text Specified value 13: Vehicle speed approx. vehicle speed
6. End diagnosis and switch ignition off.

If no speed is displayed

The speed signal is transferred from the Engine Control Module (ECM) to the instrument cluster via wire connection or via CAN-Bus, depending on version.

1. Checking wire connections
2. Check terminal resistance for CAN-Bus. See «TERMINAL RESISTANCE FOR CAN-BUS, CHECKING»(/audi/s6/c5-1999-2004/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-42l-v8-5v-art-awn-bbd__terminal-resistance-for-can-bus-checking) .

After repair work, the following work steps must be performed in the mentioned sequence

1. Check DTC memory. See «MODE 3: CHECK DTC MEMORY»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) .

Terminal resistance for CAN-Bus, checking

The Engine Control Module (ECM) communicates with all databus-capable control modules via a CAN-Bus.

These databus-capable control modules are connected via two data bus wires which are twisted together (CAN_High and CAN_Low), and exchange information (messages). Missing information on the CAN-Bus is recognized as a malfunction and stored.

Trouble-free operation of the CAN-Bus requires that it have a terminal resistance. This central terminal resistor is located in the Engine Control Module (ECM).

1. VAG1526A hand multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Ignition switched off.

1. Connect test box to the Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/s6/c5-1999-2004/remont/testing-diagnostics/#on-board-diagnostic-obd-generic-scan-tool-42l-v8-5v-art-awn-bbd) ; wiring harness is not connected.
2. Check the central termination resistor in the Engine Control Module (ECM)
3. Connect multimeter between terminal 58 and 60 of test box for resistance measurement. Specified value: 60 to 72 ohms

If the specification is exceeded or not met

1. Replace Engine Control Module (ECM).

If specified value is obtained

1. Disconnect test box from Engine Control Module (ECM).
2. Connect test box to control module wiring harness.
3. Check CAN-Bus wires for short circuit to each other
4. Connect multimeter between terminal 58 and 60 of test box for resistance measurement. Specified value: INFINITY ohm (no continuity)
5. If necessary, repair wire connection according to wiring diagram.

See also:
• READINESS CODE, GENERATING
• TELEMATICS, ON BOARD DIAGNOSTIC (OBD)
• THROTTLE POSITION (TP) SENSOR, CHECKING
• MALFUNCTION LAMP FOR ON BOARD DIAGNOSTIC (OBD)/MALFUNCTION INDICATOR LAMP (MIL) -K83- IN INSTRUMENT CLUSTER
• ELECTRONIC POWER CONTROL (EPC) WARNING LAMP -K132- IN INSTRUMENT CLUSTER
• SECONDARY AIR INJECTION (AIR) SOLENOID VALVE -N112- CHECKING
• CHECK CAMSHAFT POSITION (CMP) SENSOR
• IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING
• BRAKELIGHT SWITCH
• MODE 3: CHECK DTC MEMORY
• MODE 4: RESET/ERASE DIAGNOSTIC DATA
• MODE 1: CHECK MEASURED VALUES
• DRIVER'S STORAGE COMPARTMENT, REMOVING
• EXHAUST SYSTEM, CHECKING FOR PROPER SEAL
• CHECKING SECONDARY AIR SYSTEM FOR PROPER SEAL
• MOTRONIC ENGINE CONTROL MODULE (ECM) -J220-, REPLACING
• Component location of brake light switch -F- and brake pedal switch -F47-, clutch vacuum vent valve switch -F36
• Component location Fuel Pump (FP) Relay -J17
• FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING
• Component locations in E-box, plenum chamber
• Component location, Throttle Position (TP) sensor -G79- and sender 2 for accelerator pedal position -G185
• ENGINE COOLANT TEMPERATURE (ECT) SENSOR -G62-, CHECKING
• THROTTLE VALVE CONTROL MODULE -J338-, CHECKING
• Component location of Secondary Air Injection (AIR) Solenoid Valve -N112
• Component location of Camshaft Position (CMP) Sensor -G163
• REPLACING ENGINE CONTROL MODULE (ECM)
• CHECKING WIRE CONNECTIONS
• OVERVIEW OF COMPONENT LOCATIONS
• CHECK VOLTAGE SUPPLY FOR FUEL PUMP (FP) AND COMPONENTS
• FUEL INJECTORS, REMOVING AND INSTALLING
• INSTALLING
• CHECKING PRIMARY VOLTAGE
• OXYGEN SENSORS AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER, CHECKING
• SAFETY PRECAUTIONS
• TERMINAL RESISTANCE FOR CAN-BUS, CHECKING