Body Electrical Control Systems - Overview BMW M3 E46

Introduction

The driver information system is presented to the driver in two main areas, the instrument cluster and the center console area. The E46 makes extensive use of bussing for communication between control modules and reduction in wiring.

The instrument cluster in the E46 is similar in design to the basic cluster installed in the E39.

It uses the pictogram display block for check control and lamp failure warnings.

Scheme 121

The Bus links used in the E46 include

The K-Bus: For communication between all body modules and driver information systems.

The CAN Bus: For communication between the engine management control modules and the instrument cluster.

The D-Bus: For diagnostic communication between the vehicle and the DIS and MoDiC testers.

Scheme 122

E46iC BUS System

The Bus system of the E46iC continues to use the K-Bus as the main communication link between body and driver information modules. The Convertible Top Module (CVM) is added to the K-Bus for communication with the GM V for top operation and the Instrument Cluster for diagnostic purposes. The addition of memory functions for both outside mirrors has required memory modules to control the operation. These modules are also connected to the K-Bus for communication with the Seat Memory module.

As with other MRS III systems, the MRS module is now connected to the K-Bus for coding/diagnostic and communication with the other control modules.

Scheme 123

Signals Which Arrive At The Instrument Cluster Via The K-Bus

SIGNALS WHICH ARRIVE AT INSTRUMENT CLUSTER VIA K-BUS

Signals Which Arrive At The Instrument Cluster Through The Can-Bus

SIGNALS WHICH ARRIVE AT INSTRUMENT CLUSTER THROUGH CAN-BUS

Instrument Cluster

The instrument cluster uses analog gauges for display of engine and road speed, engine temperature, fuel level and economy display.

Scheme 124

There are three LCD blocks for display of

1. The Check Control - Pictogram
2. The BC/SERVICE Interval And Mileage
3. The Transmission - Range/Program And Failure Display

Warning indicators and lamps are arranged to the right and left of the LCD blocks. The ASC, charge indicator, high beam and oil pressure lamps are located between the speedometer and tachometer.

Features of the E46 cluster include

1. Stepper Motor Drives For The Analog Gauges
2. New Design Service Interval Indicator (SIA IV)
3. Automatic Transmission Range/Program Display

The instrument cluster is a sealed unit and contains no serviceable components, other than the back lighting illumination bulbs.

Check Control LCD Matrix Display

The pictogram check control display carries over from the E39 for failure display warnings of various lights, doors/trunk open and low fluid indications. Inputs for warning lamp indication are processed by the cluster electronics and the appropriate LED is illuminated.

Scheme 125

Range/Program Matrix Display

The right LCD matrix is used to display the driving range and program on vehicles equipped with an automatic transmission. The transmission fault display is also integrated into the display matrix. The gear with the explanation point will illuminate when the electronic control of the transmission detects a fault.

Scheme 126

Dynamic Digital Inputs

DISTANCE SIGNAL - This input is supplied to the cluster by the ABS/ASC+T control module as a square wave signal. Pulses from the left rear wheel speed sensor are processed by the ABS module to produce this signal. The cluster electronics process the input for the cluster display and pass the signal along, on the K bus, as speed signal "A" for other control modules requiring the vehicle speed signal.

CAN BUS SIGNALS - The "Ti", engine temperature and "TD" signals are produced by the DME control module and sent to the cluster. The cluster also passes the TD signal out over the K Bus.

TRANSMISSION DATA - The AGS control module provides the range selector position, driving program and fault lamp activation signals to the cluster over the CAN line.

Scheme 127

OIL TEMPERATURE - This input is a pulse width modulated signal from the Electronic Oil Level Sensor. As oil level decreases the pulse width of the signal increases. If the signal shows an oil level that is too low over a period of time, the instrument cluster will illuminate the Oil Warning indicator LED in yellow.

DIMMER SIGNAL - This is a pulse-width modulated signal from the LSZ. It is used to control the intensity of the back lighting of the instruments and the LCDs when the lights are switched ON. This signal is also output over the "K" Bus.

K-BUS SIGNALLING - The Cluster receives signals for the Check Control Pictogram over the K-Bus.

Analog Input Signals

BATTERY VOLTAGE - Battery voltage is monitored by the cluster and a fault is stored if the voltage exceeds 16 volts.

FUEL TANK LEVEL - Two lever action sensors are wired in parallel to the cluster. The two varying voltage signals are processed by the cluster for fuel gauge and low fuel warning display.

Scheme 128

OUTSIDE TEMPERATURE SENSOR - A NTC sensor is used to measure the ambient temperature. The signal is processed by the cluster and passed out over the K Bus to modules requiring this input for processing.

Digital Input Signals

The normal ignition switch terminals (KL R, KL 15 & KL 50) are input to the cluster. Various functions are dependent on ignition switch position.

STEERING COLUMN SWITCH - As with previous systems the turn signal stalk is used to call up BC functions.

BRAKE PAD WEAR SENSORS - The pad sensor inputs are used to illuminate the brake pad warning indicator as in the past.

Scheme 129

INSTRUMENT PANEL BUTTON - The reset button is used to reset the trip - odometer as in the past. It will also display the mileage, if pressed with the key switched OFF. This button is also used for the Base BC/instrument cluster test functions.

INPUTS FOR WARNING LAMPS - Various switches are used to signal the cluster for warning and indicator lamp illumination including

WARNINGS FOR CONVERTIBLES

1. The seat belt warning lamp is illuminated when the seat belt is not fastened and FLASHES when the front seat back is not locked into position.
2. The Roll over Protection System warning lamp is illuminated when there is a fault in the RPS system.

Output Signals

SPEED SIGNAL "A" - The vehicle speed signal is available as an output for control modules that require precise vehicle speed information.

"K" BUS INTERFACE - The K Bus is used to transfer data between the cluster and other modules on the link. The diagnostic interface also passes over the K Bus for troubleshooting with the DIS Tester.

LOW FUEL - Based on the processing for the low fuel indicator lamp, this output is also sent to the DME control module. The signal is stored along with a mis-fire detection fault for troubleshooting purposes.

GONG OUTPUT - T3, The T3 tone is used for check control warnings.

Scheme 130

Redundant Data Storage

Specific information is stored redundantly in the instrument cluster and in the Light Switch Module. The data stored redundantly includes

1. VIN
2. Total Mileage
3. Service Interval Data

The redundant storage of this information allows for the replacement of a module without the loss of the total mileage accumulated or the loss of the SI data.

Scheme 131

The data is compared each time KL 15 is switched on. If the data does not match, the manipulation dot in the mileage display block will be illuminated.

The following points must be noted with regards to the redundant storage of this data.

1. If the vehicle ID number is not the same in both modules, the manipulation dot is illuminated. All functions of both modules continue to operate.
2. Data will only be transferred from the LSZ to the cluster if the ID numbers match and the cluster mileage is zero.
3. The VIN is entered in the cluster through coding and will only be accepted when the cluster mileage is zero.
4. The stored mileage in the LSZ can only be overwritten by a higher mileage.
5. If the two mileage values stored vary by more than 120, and the VINs are the same, the cluster will continue to accumulate mileage and a fault will be stored in the cluster for data transfer.
6. If the K-Bus link fails, the cluster will continue to store mileage and set a fault for the Bus link.

New components should only be installed for replacement purposes and not for use as test components for diagnosis as miles will accumulate if the vehicle is driven for road testing purposes.

Scheme 132

SIA IV

Models: E46

Production: From start of production

Scheme 133

SIA IV Components

1. Instrument Cluster with LED display
2. DME
3. Vehicle Speed Signal

Instrument Cluster (IKE, KOMBI) with LED Display

The Instrument cluster calculates the Service Interval. The cluster is also responsible for displaying the mileage reading for the next service.

DME

The DME provides the Fuel Consumption (Ti) signal.

ASC/DSC Control Module

The vehicle speed signal is provided by the ASC or DSC control module.

Principle of Operation

Starting with the E46 a new method for displaying the Service Interval is used. Colored LEDs are no longer used to display the amount of time until the next service or inspection is due.

With the SIA IV system, the actual mileage remaining until the next service will be displayed for five seconds when the ignition is first switched on.

Scheme 134

The text "OIL SERVICE" or "INSPECTION" will also illuminate to show which service is due.

A minus symbol (-) before the mileage display indicates that a service is past due.

The calculation process for determining the service interval is similar to SIA III. A set volume is stored in the Cluster. The processor receives the Ti signal from DME as the vehicle is driven. The Cluster also receives the vehicle speed signal from the ASC/DSC control module.

Based on the amount of fuel consumed and the distance traveled, the processor calculates the distance remaining to the next service.

Workshop Hints

Reset of the SIA can be done using special tool 62 1 110 if the vehicle is equipped with the 20 pin under-hood diagnosis connector.

On 2001 MY vehicles onward without the diagnostic connector in the engine compartment, the use of the S.I reset tool is not possible. The Service Indicator may be reset using the Reset Mode in the Instrument Cluster or with DIS.

Reset Procedure Using The Reset Mode. (Possible From 9/99 Onward For E46, My 2001 E52)

1. Ignition key must be "off".
2. Press and hold the trip odometer button in the instrument cluster (left button), and turn the ignition key to the first position (KLR).
3. Keep the button pressed for approximately 5 seconds until one of the following words appear in the display: "OIL SERVICE, or "INSPECTION", with "reset".
4. Release the reset button and press and hold it again until "reset" begins to flash.
5. While the display is flashing, press the left button briefly to reset the service interval. After the display has shown the new interval, the following will appear: "END SIA".

The system can only be reset again after 10 liters (2.5gal) of fuel have been consumed.

Scheme 135

Reset Using Diagnosis Program (DIS)

1. Connect the Diagnosis head to the diagnostic connector of the vehicle.
2. Identify the vehicle and perform the Short Test.
3. Select Function Selection and then Service Functions.
4. Highlight Reset Service Interval Indicator (Test module S6211-00001).
5. Select with tester.
6. Follow the directions from the help information in the test module (upper right corner).
7. Select which service is to be reset and press the continue key.
8. An acknowledgment is displayed on the screen that the reset has been carried out.

Instrument Cluster Replacement

If the instrument cluster (Kombi) is replaced the SI data can be retrieved from the LSZ on E46 vehicles and from the LCM III on the E52. Coding procedures are the same as SIA II.

Diagnosis

Diagnosis of the SIA System is carried out using the Diagnosis program of the DISplus or MoDiC III.

Scheme 136

On Board Computer

The On Board computer of the E46 contains the following functions

Scheme 137

1. Time
2. Outside Temperature
3. Average Fuel Consumption
4. Driving Range On Remaining Fuel
5. Average Speed

The current time is always displayed when KL R is switched on. Any other BC display value can be called up by pressing the turn signal lever.

To set the clock "turn" the odometer reset button to the left or right to set the desired time.

To reset any other programmable displays - hold the turn signal lever in for more than 2 seconds.

A freeze warning is incorporated into the BC. If the temperature drops below 37 degrees, the gong will sound and the temperature display will flash.

The displays of the Board computer can be changed over from Fahrenheit to Celsius by pressing the instrument cluster button and switching the ignition key on. IHKA display will also change over. The average fuel consumption and average speed displays are reset by pressing and holding the turn signal lever for more than 2 seconds. The BC then starts to calculate new average values.

Instrument Cluster Test Functions

In addition to the fault memory and diagnostic link, the base instrument cluster contains a series of test functions that can be accessed to check various functions and values. The test functions are displayed in the mileage LCD block. There are a total of 21 test functions.

The test functions are similar to those of previous Board computers and contain similar tests.

Scheme 138

1. Tests 1 & 2 are always unlocked.
2. Tests 3 -21 are only accessible after unlocking the test function. Test 19 is the unlock function for accessing the displays.

Scrolling through the numbered test functions is achieved by pressing the instrument cluster button.

The button is either momentarily pressed (tapped) < 1 second or pressed and held for > 1 second.

This signals the BC to display the sub-tests of the displayed main test menu or continue on to the next main test menu.

1. TEST 01. - Vehicle specific data including: SubTests: 12345 1.0 = VIN 4812 1.1 = Body number 834762 6_1.2 = Part number of cluster 010203 1.3 = Coding/Diagnosis/Bus index 3495 1.4 = Manufacturing date (calendar week/year) 04_600 1.5 = Hardware/software # of cluster (HW:04, SW:6.00) 415_06 3_1.6 = Injection status, number of cylinders, engine factor
2. TEST 02. - Cluster System Test - activates the gauge drivers, indicators and LEDs to confirm function.
3. TEST 03. - SI data Sub Tests: 1500 3.0 = Liters 0 3.1 = Periodic inspection days (not applicable for US).
4. TEST 04. - Momentary Consumption Sub Tests: 0267 4.0 = 26.7 liters/1000km 0073 4.1 = 7.3 liters per hour
5. TEST 05. - Distance Gone Consumption Sub Tests: 0195 5.0 = 19.5 liters/100 km 226 5.1 = momentary distance to go (226km)
6. TEST 06. - Fuel level sensor inputs in liters Sub Tests: 237415 6.0 = Fuel level averaged LH sensor input = 23.7 liters RH sensor Input = 41.5 liters 0652 6.1 = Total tank level averaged = 65.2 liters 0667 1_6.2 = Indicated value and tank phase 1 = both sensors OK 2 = one sensor fault 3 = implausible input
7. TEST 07. - Temperature and Speed Sub Tests: 032 7.0 = Coolant temp input 32°C 245 7.1 = Outside temp input 24.5°C 5283 7.2 = Engine speed 5,283 RPM 058 7.3 = Vehicle speed 58km/H
8. TEST 08. - Input values in HEX form Sub Tests: XXX 8.0 - 8.3 = Hex code, Instrument cluster inputs
9. TEST 09. - Battery voltage Sub Tests: 125 9.0 = 12.5 volts
10. TEST 10. - Country Coding Sub Tests: 02 10.0 = US 02
11. TEST 11. - Cluster code Sub Tests: 000003 11.0 = Cluster code
12. TEST 12. - Not Used
13. TEST 13. - GONG test Sub Tests: Gong 13.0 = Activate gong by pressing button (gong response is delayed).
14. TEST 14. - Fault memory (not for diagnosis)
15. TEST 15 to 18 - Not used
16. TEST 19. - LOCK/UNLOCK Sub Tests: L-ON... L-OFF 19.0 = Display changes from "L-ON" to "L-OFF" every second. To unlock test functions, press the cluster button immediately when it changes to "L-OFF". Tests are automatically locked when exiting test functions.
17. TEST 20. - Not Used
18. TEST 21. - Software reset Sub Tests: reset 21.0 = Reset software

LIGHT SWITCH CENTER (LSZ)

The Light Switch Center is a compact component that combines the electronic control, switching, and monitoring for all exterior lighting on the E46. In addition the LSZ controls the illumination and intensity of the instrument cluster lighting and LCD blocks. The LSZ assembly is mounted in the dash and consists of two serviceable components; the switch assembly and the control module.

LSZ Functions

The LSZ provides the functions of the LCM including

Scheme 139

1. Hot and cold monitoring of the exterior lights.
2. Emergency lighting function
3. Short circuit protection
4. Redundant storage of mileage and SI data

The total scope of the LSZ system includes the following

Scheme 140

1. LSZ control module
2. LSZ switch assembly
3. High-low beam/turn signal switch
4. Brake light switch
5. Hazard warning light switch
6. Fog light relay
7. Exterior lights
8. Dash/LCD lighting

Component Operation

The LSZ control module receives inputs from the following switches

Headlight/parking light switch, fog light switch, potentiometer and photo-transistor mounted in the LSZ switch assembly.

1. These inputs are received directly from the LSZ switch assembly.

Turn Signal/Highbeam Switch

1. The turn signal and headlight (high/low) beam are resistance coded inputs over two wires to the LSZ control module. The LSZ carries out the switching function based on the voltage drop input.

Hazard Warning Switch

1. The hazard switch provides a ground input to the LSZ to control the operation of the hazard warning lights.
2. The hazard warning lights will be switched on in the event of an accident from the crash sensor input provided by the MRS control module.

Brake Light Switch

1. The brake light switch is a hall sensor that receives power when KL R is switched on. The switch is low until the brake pedal is pressed. When the LSZ receives a high signal from the switch the brake lights are switched on.
2. If the hall sensor fails, the brake lights will be switched on continuously.

E46 Convertible Third Brake light

The E46iC uses Neon technology for the third brake light which is mounted in the trunk lid.

The remainder of the exterior lighting circuits carry over from the E46 Sedan and Coupes. The Electronic brake light switch is the input to the LSZ for brake light activation.

The LSZ, as an output, provides power to the Neon light module for activation of the light.

The light module consists of the ignitor, and Neon tube.

The use of neon lighting provides several advantages to automobile manufacturers and consumers

Light failures caused by shock and vibration are minimized, because neon operates without a filament.

The average life of the light is considerably higher as compared to incandescent bulbs.

Styling of the light includes a more uniform distribution of light across the lens, and neon tubes can be bent to conform to the contour of the vehicle.

Amber neon allows the use of a clear lens (for vehicle color schemes).

Neon enhances safety because of the extremely fast ignition time of the light (instantaneous braking signal), allowing other drivers more time to react.

Neon Technology

Neon (symbol Ne) produces a glow in a vacuum electric-discharge tube and is used extensively in the familiar advertising displays.

Scheme 141

A neon light is a glass bulb or tube containing neon (gaseous element) at low pressure, and two metallic electrodes. To make a neon light, the tube is bent while warmed, to the desired shape and sealed at both ends. During the sealing process, electrodes are added at each end. An access port is left near one end and a vacuum is applied to the interior of the tube. After the air and humidity has been removed, the neon gas is added under low pressure and the tube is sealed.

The light produces a reddish-orange glow when an electric current (applied across the electrodes) is raised in voltage to the point at which it ionizes the gas in the tube. The voltage at which the light glows varies with the design of the tube. When the glass tube is ionized, the voltage drop across the tube is constant, regardless of the amount of current flowing through the tube. The neon glows with an even intensity throughout the length of the tube.

A variant of this is the glass tube containing ionized neon at very low pressure. The tube shines with a brilliant red glow if a high-voltage alternating current is applied to the electrodes sealed in the ends of the tube.

Lamp Monitoring

Lamp monitoring on the E46 is a function of the LSZ control module. The following lamps are monitored in both the hot and cold states

1. High/Low Beams
2. Brake Lights - Left/Right
3. Turn Signal Lights
4. Tail Lights
5. Parking Lights
6. Side Marker Lights
7. License Plate Lights

Hot monitoring takes place when the lights are switched by monitoring the current flow through the lamp filaments.

Cold monitoring takes place by the LSZ when the lights are switched off. The LSZ will briefly activate the lighting circuits and check for current flow through the lamps. The lights are not switched on long enough to illuminate the bulbs.

If the LSZ detects a defective bulb, a signal is sent to the instrument cluster and the warning is posted in the Check Control pictogram.

Scheme 142

Scheme 143

Home Lighting

This convenience feature provides lighting for the driver and passengers to leave the vehicle and enter their house.

The feature is switched on by activating the headlight flasher switch after the lights and ignition are switched off.

Scheme 144

The feature is switched off after the coded time delay or by switching the ignition switch on.

Redundant Storage

The LSZ serves as the redundant storage module in parallel with the instrument cluster.

This includes all data used for vehicle identification which is encoded on the assembly line.

In addition the total mileage and SI data are also stored in the LSZ.

If either the Cluster or LSZ has to be replaced, the data is taken from the remaining module and transferred to the replacement unit. This can only occur ONCE the VIN has been entered into the replacement unit. Once the VIN is entered, the module becomes part of the vehicle and can not be interchanged with another vehicle.

Emergency (Fail Safe) Lighting

The LSZ provides emergency lighting in the event of a control module failure. If the processor of the LSZ control module fails, back up hardware will allow the following lighting circuits to function

1. Low Beam Headlights
2. Tail Lights
3. Parking Lights
4. Brake Lights

The headlights and tail lights will come on as soon as KL 15 is switched on, the brake will operate when the brake pedal is pressed.

Scheme 145

The automotive industry/press often identify xenon lighting systems as HID (high intensity discharge) systems. Xenon headlight technology was first introduced to the US market exclusively on the E32 750iL in 1993. BMW xenon headlight systems have evolved and their availability as optional equipment has spread throughout the model lineup.

Blue/White in color and using ellipsoidal technology Xenon headlights provide improved night time visibility in all driving conditions compared with traditional Halogen bulb headlights.

Benefits

Xenon headlights provide the following benefits

Scheme 146

Scheme 147

1. Longer Bulb Life - Typically, xenon bulbs will last from 3 to 5 times longer than halogen.
2. More Light Output - Xenon headlights produce from 2.5 to 3 times more lumens than halogen.
3. Blue/White Light (simulates natural daylight) - Xenon bulbs produce a blue/white light while halogen bulbs produce a yellow light. The light color of a light source is measured in color temperature (not to be confused with thermal temperature). Color temperature is measured in Kelvins (K). The higher the color temperature the whiter the light. Natural daylight = 4,500 to 5,000 K Xenon headlights = 4,000 to 4,500 K Halogen headlights = 3,200 K (yellow in color)
4. Better Driving Visibility - The combination of higher lumens and higher color temperature provide a superior lighting source. The beam is wider and brighter in front of the vehicle than conventional halogen bulbs improving safety and driver comfort.

Version Identification & System Summaries

Version identification is specific to vehicle model with the exception of the E38.

There are two E38 Xenon systems. The early system identified as Generation 2.1 and equipped on 95-98 model year 750iL vehicles. The headlight design of this version has a flat bottom edge.

The Generation 3 system has been introduced on 1999 model year E38 vehicles. This system can be visually identified by the rounded bottom edge of the headlight assembly.

Scheme 148

LWR: All 1999 model year systems are also equipped with LWR (Headlight Beam Throw Control). This system automatically adjusts the vertical position of the headlight beams to compensate for vehicle loads ensuring optimum beam throw. LWR components and function is described further on in this section.

Headlight Replacement Parts: In previous model years, individual replacement parts were not available for headlight assemblies. This was due to the Federal Motor Vehicle Safety Standards (FMVSS) relating to pitting or corrosion of the reflector components in non-sealed beam light assemblies.

BMW has submitted corrosion test data for headlight replacement components which have passed the FMVSS providing availability of headlight assembly spare parts. The approval has been given for all Bosch headlight assemblies (including halogen systems).

BMW CORROSION TEST DATA FOR HEADLIGHT REPLACEMENT COMPONENTS

Xenon High Intensity Discharge Bulbs

Xenon bulbs are identified as D-2S (D=Discharge).

Xenon bulbs illuminate when an arc of electrical current is established between two electrodes in the bulb.

The xenon gas sealed in the bulb reacts to the electrical excitation and heat generated by the current flow.

The distinct bluish/white brilliant light is the result of the xenon gas reacting to the controlled current flow.

Scheme 149

Phases of Bulb Operation

Starting Phase: The bulb requires an initial high voltage starting pulse of 18-25kV to establish the arc.

Warm Up Phase: Once the arc is established the power supply to the bulb is regulated to 2.6A generating a lamp output of 75 watts. This is the period of operation where the xenon gas begins to brightly illuminate. The warm up phase stabilizes the environment in the bulb ensuring continual current flow across the electrodes.

Continuous Phase: Once the warm up phase is completed, the system switches to a continuous mode of operation. The supply voltage for the bulb is reduced and the operating power required for continual bulb illumination is reduced to 35 watts which is less than a conventional halogen bulb.

Functional Description

To regulate the power supply to the bulbs, additional components are required. The xenon control modules (1 per light) receive operating power from the lighting control module (LCM E38/E39 - LSZ E46) when the headlights are switched on. The xenon control modules provide the regulated power supply to illuminate the bulbs through their phases of operation.

The igniters establish the electric arcs. Integral coils generate the initial high voltage starting pulses from the control module provided starting voltage. Thereafter they provide a closed circuit for the regulated power output from the control modules.

Scheme 150

Xenon Bulb Monitoring

Xenon bulb function is monitored by the Lighting Control Module (LCM E38/E39 - LSZ E46). The bulbs are only "hot" monitored. Cold monitoring is not possible since the lighting control module is not in direct control of the xenon bulb. For this reason cold monitoring for low beam headlights is encoded off in the lighting control module for Xenon headlight equipped vehicle.

The lighting control module detects xenon bulb failure via a reduction in current flow to the xenon control module. When a bulb fails, the xenon control module's current consumption drops to 60mA indicating unsuccessful xenon bulb illumination. The lighting control module then posts the appropriate matrix display message or LED illumination in the Check Control Pictogram display of the E46 and E39 Low Instrument Clusters.

Xenon control modules are not connected to the diagnostic link. However, the vehicle specific Lighting Control Module (E38/E39 - LCM or E46 - LSZ) does incorporate xenon headlight specific diagnosis up to the xenon control module.

Xenon Headlight Testing

All xenon headlight systems (control module, igniter and bulb) can be tested with Special Test Adapter (P/N 90 88 6 631 000) in conjunction with the DIS Measurement System only.

The DIS Measuring System includes all of the cable connection information and test procedures in the "Xenon Preset Measurement".

Scheme 151

The test provides an automatic oscilloscope setup and provides conclusive "defective/not defective" test results.

Xenon Headlight SI/TRI Bulletins

1. SI 6308 98: Xenon Headlamp Reduced Service Life - 1999 740iL. This bulletin address a small group of possibly defective xenon control modules. This bulletin uses the special test adapter and specific oscilloscope setup procedures to check the xenon control module output.
2. SI 63 02 98 : E39 Headlight Alignment Procedure
3. SI 63 02 93: Xenon Headlights - Color, Fuses, Warranty
4. TRI 63 01 92: Gas Discharge Xenon Low Beam Headlights.

LWR automatically adjusts the vertical positioning of the headlights to maintain optimum headlight beam positioning for maximum driving visibility and to prevent undue glare for oncoming motorists. The system compensates for vehicle load angle changes (i.e.: diminishing reserve of gasoline in fuel tank during a long journey, overloaded cargo weight, etc.)

LWR has been available on BMW vehicles in other markets for quite some time. Starting with the 1999 model year all US market vehicles with Xenon Lights incorporate LWR as standard equipment. LWR is not available with standard halogen headlights.

LWR monitors the vehicles loaded angle via two hall effect sensors mounted to the front and rear suspension members. When an adjustment is necessary, LWR simultaneously activates two stepper motors (one in each headlight assembly).

The stepper motors drive a threaded rod that moves the lower edge of the headlight carrier plate forward and backward (depending on driven direction). The upper edge of the headlight carrier plate is fixed on a pivot. The pivoting movement adjusts the vertical position of the headlight beam.

Scheme 152

Note. LWR is identified in the Diagnosis Program as LRA.

LSZ - E46

The E46 LWR function is integrated into the control electronics of the LSZ. The LSZ monitors the required input signals to provide the LWR function and directly activates the stepper motors in the headlight assemblies. All LWR diagnosis is accessed through the LSZ control module.

Level Sensors

LWR monitors two hall effect level sensors to determine vehicle load angle. The sensors are mounted to a fixed point on the suspension carriers of the front and rear axles.

A lever is connected to the moving suspension member which changes the sensors output linear voltage signal as the suspension moves up and down.

Scheme 153

Headlight Adjustment Stepper Motors

One stepper motor is located inside each headlight assembly.

The 4 wire stepper motors are controlled by the LWR control electronics to change the vertical headlight position.

Scheme 154

The E46 LWR system comes on-line when the ignition switch is turned to KL 15.

The LWR control electronics then cycles the stepper motors through their full range of motion and stops at a default position.

The control electronics monitors the level sensor input signals to determine the vehicles load angle and adjusts the beam position accordingly. As the vehicle is driven it continually monitors the level sensor signals and if necessary updates the headlight beam positions every 25 seconds.

Abrupt fluctuations of the sensor signals are filtered to prevent unnecessary adjustment as well as monitoring road speed.

Headlight Alignment

The procedure for aligning Xenon Headlights with LWR is the same as conventional halogen bulb systems with one additional step. Wait at least 30 seconds for the LWR to cycle and adjust to it's calculated position.

LWR Diagnosis

The E46 LSZ incorporates LWR diagnosis program.

Scheme 155

MULTI-FUNCTION STEERING WHEEL

The multi-function steering wheel of the E46 corresponds to the MFL introduced on the E38 and carried over to the E39. The wheel contains two key pads on the left and right side of the air bag that allow activation and control of various driver convince systems.

As with previous MFLs, the left side key pad contains controls for the sound system and telephone. The right side key pad contains the controls for the cruise control.

Scheme 156

The K-Bus is used for data communication between the sound system/telephone controls.

The cruise control has its own data link to the DME control module for cruise control operation.

SOUND SYSTEMS

Two different sound systems were available for the E46 at the start of production. The standard radio features the in-dash cassette player and the optional radio has a single in-dash CD player. Both radios are prewired for the optional CD changer that mounts in the trunk.

Scheme 157

The sound systems for the E46 continue with the integration feature introduced with the E38. The sound system is interconnected on the K-Bus for amplifier and MFL communication.

Theft proofing of the radio via a code is no longer required as the radio will not function without the K-Bus connection and a valid K-Bus signal from the instrument cluster.

Scheme 158

Antenna Configuration

The sound systems available for the E46 Sport Wagon are the same as the systems installed in the E46 Sedan and Coupe. The following antenna layout is used for the Sport wagon body

1. FM 1 - Rear window on the right side
2. FM 2 - Rear window in the center
3. FM 3 - Left rear side window
4. AM - Rear spoiler
5. FZV - Combined with FM 2 antenna

The amplifier for FM 1 and FM 2 antennas is located beneath the rear spoiler. The signal from the antennas passes from the amplifier to the diversity module located in the left side storage compartment.

Scheme 159

Scheme 160

The FM 3 antenna has a separate amplifier that is integrated into the diversity module which is mounted behind the storage cover on the left side.

Scheme 161

Diversity Switching

The FM1/FM2 amplifier can only send one FM signal at a time. The diversity module controls the switching of the signals by applying a voltage signal to the RF cable. When the voltage signal is low, the amplifier sends the FM 1 signal.

When the voltage level is high, it sends the FM 2 signal. The FM 1 and FM 2 inputs are continuously checked for the clearest signal.

The diversity module then checks the signal from FM1/FM2 with the signal from FM 3. The clearest of these signals will always be sent to the radio for FM reception.

Scheme 162

FZV Antenna

The RF receiver module (315MHz) is integrated into the antenna amplifier. The receiver has a separate KL 30 power supply for its operation. Signal from the FZV key are processed by the module and sent to the GM for locking/unlocking functions over a dedicated line.

Audio System Speakers

The rear speakers for the sound system are mounted on the left and right wheel housing behind the trim covers

Scheme 163

If the Navigation system is installed in the Sport Wagon, the GPS receiver module is installed under the load floor in front of the spare tire well.

Scheme 164

Convertible Sound System

The audio systems available for the E46iC correspond to the systems available in the E46 Coupe. Two radios, with either the in dash CD player or cassette player are available. The navigation system with the board monitor is optional equipment. All sound systems are prewired for the optional CD changer that mounts in the trunk. The sound systems continue to be interconnected on the K-Bus and all radio test functions carry over.

Scheme 165

Scheme 166

Scheme 167

Harman/Karden Sound System

Speaker and component locations will vary depending on the type of sound system installed. Four rear speakers are mounted in the rear side trim panels, two on each side (one wide band 130 mm and one tweeter dome).

Scheme 168

The Harman/Karden system incorporates an additional Subwoofer is installed in the trunk in the ski bag cover.

The subwoofer is 200 mm diameter without a subwoofer amplifier. The amplification for the subwoofer comes from the main sound system amplifier.

Scheme 169

The subwoofer is hinged so that it will swing to the side when the ski bag is used. A magnet on the subwoofer cover will hold the subwoofer in place against the rear bulkhead while the ski bag is being used.

The subwoofer will continue to function in either position closed/open. As mentioned, with the Harman/Karden system, the stereophonic sound is modified when the top is lowered. The sound system amplifier receives a signal from the rear window defroster relay when the top is lowered to switch the stereophonic sound off.

Scheme 170

Purpose of the System

The E46iC is equipped with a diversity antenna system to provide the sound system with the strongest possible radio station signal to receive the best performance possible from the sound system.

Components of the System

The Diversity antenna system on the E46iC consists of

1. Main antenna mast - mounted on the left rear fender.
2. Diversity antenna - mounted in the top storage cover.
3. Main antenna amplifier - mounted directly below the antenna mast
4. Auxiliary antenna amplifier - mounted on the top storage cover.
5. Diversity switching module - mounted below the antenna mast in the trunk.

The telephone antenna is wound around the main antenna mast.

Scheme 171

The second antenna for the FM diversity system is integrated in the convertible top storage cover. The FM2 antenna incorporates a separate amplifier that receives its power through the antenna lead.

Scheme 172

Scheme 173

System Operation

Both antennas receive the signals for radio reception. Each signal is amplified by its own antenna amplifier and the signals are passed two the diversity switching module. The diversity module will lock onto the stronger of the two signals and send it to the radio receiver for sound system operation.

Starting September 2000, a family of new generation radios will begin to be phased into production. The exception to this is the E52 which has been available with the MIR (multi-information radio) NG radio since series launch in mid 2000.

The NG "New Generation" radios will have increased functions

1. Radio can be operated without KL R.
2. Radios are world frequency.
3. Car memory programming.
4. Audio mixing on vehicles equipped with navigation.

The radios external appearance has not changed. NG radios can be identified by their "53" designation.

Overview of the Radios for Each Model

OVERVIEW OF RADIOS FOR EACH MODEL

NG Radio System Overview

Note. Example: E39 with MK III navigation and BMBT.

Scheme 174

NG Radios

Radio Operation with KL R off

Operation is possible with the key off on the C53 and CD 53 radios. If the radio is turned on with KL R off, it will play at the last stored volume and settings for 16 minutes until the General Module sends the sleep command. No changes may be made to the radio unless KL R is switched back on. The radio can be turned on and off as many times desired.

Diversity Antenna

Antenna diversity has been adapted to the new generation of radios. When the radio is in operation, the diversity control unit is activated by the "RAD ON" signal.

World Frequency Radio

Radios on vehicles sold in the U.S. are world radios. Specific country settings can be made using the service mode. The settings are stored in an EEPROM.

Car Memory

If programmed, when locking the vehicle using the remote transmitter the

1. Last Station
2. Volume Setting
3. Last Audio Mode (Tape, FM, CD etc.)

are stored according to the key number used. Unlocking the vehicle with the same transmitter will restore the settings. There is a maximum setting for volume which may be lower than the setting when the radio was last operated.

Clock

Time can also be displayed when KL R is off by pressing the clock button on the Radio/MID.

Backlighting

The LCM/LSZ produces two signals for the control of radio backlighting.

1. Hardwired KL 58g
2. Lights on/off over the K/I Bus.

The radio contains a photo-cell for adjustment of backlighting to ambient conditions.

Reset and Voltage Monitoring

A radio reset is triggered by under voltage or the internal processor monitor. The reset function restarts the radio, similar to turning it off and back on again. Operating voltage is measured at the KL 30 input. The radio is switched off if the system voltage exceeds 17V to protect the radio, it will switch on when the voltage falls below 16V.

GAL (Speed Dependent Volume)

The speed signal from the IKE/KOMBI is available to the radio over the K/I Bus. GAL is not a feature on vehicles equipped with DSP.

Bus Communication

The radio communicates with other modules via the K bus or I Bus dependent on the model. The information shared over the bus line includes

1. IKE/KOMBI- Terminal status (KL 15, KL R)
2. LCM/LSZ - Lights on
3. IKE/KOMBI link to TXD - Diagnosis
4. MID or BMBT - button or rotary knob status.
5. GM - Key used to lock or unlock vehicle
6. MFL - audio controls status

NG radios do not use anti-theft codes. Operation of the radio is only possible if connected to a bus line and the detection of at least one other component.

Service Mode for NG Radios

A service mode is available as on previous radios as a diagnosis tool and for changing radio settings. Entering the service mode varies by the device used to control the radio.

To enter the service mode

C53/CD53 with and without MID

1. Turn on the radio.
2. Within 8 seconds, press and hold the "m" button for 8 seconds.
3. Scroll through functions using the "+" and "-" keys or the station < > search buttons.
4. Turn off the radio to end the service mode.

C53 MIR

1. Turn on the radio.
2. Within 8 seconds, press and hold the "SEL" button for at least 8 seconds.
3. Scroll through functions using the station < > search buttons.
4. Turn off the radio to end the service mode.

BM53 with board monitor

1. Turn on the radio.
2. Press and hold the "RDS" button for at least 8 seconds.
3. Scroll through the functions using the station < > search buttons.
4. Turn off the radio to end the service mode.

BM53 with Widescreen board monitor

1. Turn on the radio.
2. Within 8 seconds, press the "INFO" button.
3. From the info screen select RDS
4. Press and hold the BM control knob for at least 8 seconds.
5. Scroll through functions using the station < > search buttons.
6. Turn off the radio to end the service mode

Service Mode Functions

1. Serial Number: Display of the radio serial number.
2. Software Version: Display of the radio software version. Displayed as (calendar week, year, version)
3. GAL: Speed-sensitive volume control. Can be adjusted from level 1-6 using the 6 preset audio buttons. Vehicles equipped with DSP do not use this feature.
4. Field strength and Quality (F/Q): The station currently displayed can be assessed for field strength and quality. An "F" (i.e. F15) number is used to indicate the strength of the signal being received by the radio. This is a good test of the antenna system, station signal, and the radio itself. A "Q" (i.e. Q-00) number is used to determine the quality of the radio station including both the audio and RDS signal if applicable.
5. DSP: This function provides information about whether the vehicle is fitted with DSP. The value is displayed as a one (fitted) or zero (not fitted) and is communicated by the DSP amplifier via the I/K bus.
6. TP Volume: Provides adjustment for traffic report minimum volume. Not used in the US.
7. AF: Alternative Frequency tracking setting. Not used in the US.
8. Area: Used to select the appropriate market setting (USA, Canada, Europe, Japan and Oceania). Adjust using the pre-set buttons.
9. Index: Display of the revision index.

Scheme 175

1. Remove center dash trim above glove box by prying off with a trim stick.
2. Remove center dash trim over radio by prying off with a trim stick.
3. Remove two screws at the top of radio assembly.
4. Slide radio forward and out of the plastic carrier.
5. Remove main radio connector by lifting connector lock to the upper most position, away from top of radio, using a screwdriver as show on connector.
6. Remove the antenna connection.
7. Install in the reverse order.

Component Overview

The E46 Mark II Navigation System is similar to E38/E39 Mark II. All of the E38/E39 Mark II system components are carried over with the exception of the BMBT

Scheme 176

1. 5 inch display (320 X 234 pixel resolution)
2. Uses on screen soft keys for telephone send/end functions. E38/E39 uses buttons.
3. Does not include auxiliary ventilation function (not a function of E46 BC/IHKA).
4. Provides display and control functions for the Audio System (radio, cassette and CD).
5. Provides display and control functions for systems in the menu display.

1999 Model Year Radio Changes

1. The 1999 model year radios do not have the weatherband feature.
2. RDS = Radio Broadcast Data System. In the future, this button will put the vehicle occupants in touch with a wide variety of broadcast data including weather information.
3. PTY = Any unit having RDS will also have a separate button for the PTY feature. It stands for Program Type and will indicate the type of music being played.

Scheme 177

The BMBT communicates with interfacing control modules via the K Bus. As with all previous Original Equipment Navigation Systems, the radio electronics are installed in the trunk. The BMBT sends and receives operation instructions to the radio via bus communication. The Mark II Nav computer continues to provide the RGB output signals to the BMBT for system function display.

E46 BOARD MONITOR & NAVIGATION SERVICE MODE DISPLAYS

The Mark II system provides a service mode display function. These screens provide system hardware/software identification numbers and status of Board Monitor and Navigation specific functions for use as a diagnostic tool. The screens are accessed as follows

1. From the Main Menu select "Set".
2. Once in the Set function, press and hold the menu button for 8 seconds.
3. The next screen to appear is the SERVICE MODE menu.

The first accessible function is "On-board monitor". Pressing this selection calls up the version screen which provides identification of hardware/software specific index versions for the installed system.

Pressing the functions key at the bottom continues into additional screens including the Key Functions and Brightness controls.

Key Functions tests the key input on the BMBT. Input status (1-25) will display in the window.

If no keys are pressed the status will be displayed as "FF".

Rotating the left or right rotary knob displays hex code input status.

Rotated slowly, the display changes with each increment.

The display eventually stops at "1F" in the left rotated direction and "E0" to the right.

The key function test terminates automatically if no keys or knobs are moved after a short duration ("00").

Scheme 178

The next accessible function is the NAVI/GRAPHIC ELEMENT.

This screen identifies hardware/software specific index versions for the installed system.

Scheme 179

The Video module selection is not functional since the US version Mark II nav system does not utilize the video module.

The next available selection from the service mode menu is "GPS".

This display provides the GPS receiver module hardware version number and date of programmed software.

Pressing the functions button in the lower right corner of this screen provides a sub-selection menu.

GPS Status provides information on the exact coordinates of the vehicle based on the calculations of the GPS receiver module.

GPS Tracking provides information about the individual satellites currently sending signals to the GPS

Scheme 180

The next selection available from the SERVICE MODE menu is "Sensor check" which provides

Scheme 181

1. Wheel speed input (only one wheel speed signal, displayed).
2. Number of satellites detected.
3. What mode the GPS receiver module is currently in; (i.e.: Search)
4. The Gyro status provides the millivoltage value the Nav computer is utilizing for the current vehicle position. This area also includes an icon representing what direction the vehicle is heading in.
5. The direction status indicates what gear is selected (forward or reverse).

The Sensor check display is intended to be used while test driving the vehicle. Use the legend below to compare with the display status.

SENSOR DIAGNOSTIC

GPS STATUS TEXT DISPLAY AND DESCRIPTION

The last selection available is the Telematics entry display. This replaces the "VIN" selection from the E38/E39 Mark II systems. The only requirement of this entry screen is that the VIN is entered at the VPC when prepped prior to distribution.

This is necessary for the Emergency program if needed when calling the Cross Country Group Roadside Assistance Program.

Scheme 182

Additionally, if the vehicle is equipped with a Phase V phone the system will automatically utilize the entered VIN as per E38/E39 Mark II systems.

The VIN is entered at the VPC for all vehicles (with or without a Phase V phone). If the VIN has been incorrectly entered it can be changed by turning and pressing the rotary knob when the correct letter or digit of the last seven character of the VIN is displayed.

The balance of the data displayed below the VIN entry is not currently used in the US market.

Mark II Navigation System Calibration

The calibration procedure of the Mark I system is not required with the Mark II system. This system self calibrates automatically as the vehicle is driven after following the steps below.

1. System must be fully functional with no faults present in fault memory.
2. Correct Map data base CD installed for your.
3. Vehicle outside with an unobstructed overhead view. Switch ignition on and allow system adequate time to receive a minimum of three GPS signals. This is confirmed by the green GPS indicator in the map display.
4. Set the map display to the 400' scale and drive the vehicle on digitized roads. Make frequent turns at intersections where possible.

While driving, the system utilizes the map CD, the received GPS coordinates, the Gyro sensor to determine turn activity and the wheel speed sensor input. It compares all of these variables and automatically pinpoints the vehicle position.

Mark II Navigation System Diagnosis

The Nav computer does not communicate with the DIS/MoDiC.

Diagnosis of the Nav Computer is performed with conventional procedures and by utilizing the Status displays on the previous pages.

Refer to the DIS for RGB output signal oscilloscope displays for visual confirmation of signal integrity.

The Board monitor (BMBT) does however communicate with the DIS/MoDiC. Follow the fault symptom path of the DIS Diagnosis Program for detailed diagnostic procedures.

Scheme 183

MK-3 NAVIGATION SYSTEM

Models: E38, E39, E46, E52, E53

Production Date: E46 from 6/00, all others from 9/00

The Mk-3 navigation system is a factory installed navigation system that replaces the previous Mk-2 version. The purpose of the system remains the same as previous navigation systems: To provide the driver with navigation instructions to an entered destination based on the vehicles current position and the roads available selected from a digitized road map.

The principle differences of the Mk-3 system over the previous Mk-2 are

1. GPS receiver is integrated into the MK-3 computer.
2. Optimized memory and faster processor resulting in faster start-up and operation.
3. New split screen and magnifying feature when equipped with wide screen monitor. (software feature)
4. Same navigation computer used for color board monitor or monochrome MIR display units.

Mk-3 Navigation Computer

The Mk-3 navigation computer is located in the left side of the vehicles trunk or cargo area.

(In the case of the Z8 it is installed in the storage box behind the passenger seat.)

The navigation computer housing contains

1. Map CD Drive
2. Hardware For Navigation Function
3. GPS Receiver
4. Gyro Sensor
5. Output For Audio Interface
6. Output For Visual Display
7. Cooling Fan For Unit

Scheme 184

There are two different hardware versions available dependent on the angle of installation in the vehicle (horizontal or vertical). The Mk-3 is compatible with both board monitor or MIR display units. (See workshop hints for configuration instructions).

Identification of the Mk-3 computer over the previous versions is easy due to a change in the face plate design and the elimination of the "CD-IN" LED.

Scheme 185

Scheme 186

Scheme 187

GPS (Global Positioning System) Receiver

The GPS receiver module of the previous Mk-2 system is integrated into the housing of the Mk-3 computer, further reducing the complexity and the number of components used in the system. The receiver is not serviceable.

The GPS receiver is responsible for receiving the satellite signals and providing the vehicles position information to the navigation computer.

Information provided by the GPS receiver to the navigation computer can be displayed in the service mode (see workshop hints) but is not typically used in diagnosis.

Gyro (Rotation) Sensor

The navigation computer contains the electronic (piezo) Gyro sensor that detects rotation (yaw) of the vehicle as a confirmation that the vehicle is turning. The signal provided by the gyro is a mili-voltage that changes as the vehicle rotates. The navigation computer uses the input to track the vehicle along the digitized map and display the exact vehicle position.

The signal is available in the sensor test page of the service mode for diagnosis. The sensor is not a separately serviceable item and does not require calibration.

GPS Antenna

The GPS antenna is directly connected to the navigation computer via a coaxial cable.

Locations of the antenna in the vehicles are as follows

E38: Under the rear parcel shelf.

E39 sedan: Under the rear parcel shelf.

E39 Sport Wagon: Behind the dashboard on the left side.

E46 sedan/coupe: Under the rear parcel shelf.

E46 Sport Wagon: Above the rear glass under the spoiler.

E46 Convertible: Behind the instrument cluster.

E52: Left front corner behind the dashboard.

E53: Above the rear glass under the spoiler.

Display Units

Based on the particular model, the factory installed Mk-3 system is displayed using a color board monitor or on a smaller monochromatic screen (MIR).

Scheme 188

Scheme 189

Scheme 190

Scheme 191

Example of E38/E39 with Mk-3 navigation

Information/Body Bus Interface

The navigation computer is integrated into the vehicle bus system as it's main communication link with the vehicle.

Communication occurs with the following modules

1. BMBT - Control Inputs
2. Radio - Display Data
3. GM - Door Open
4. IKE/Kombi - On-Board Computer Data
5. Telephone PSE Box - Monitor Display Data, Mayday Function
6. DISplus - Coding Data

PSE = Portable Support Electronics

Board Monitor (Top Navigation)

The RGB video signal for all display functions of the board monitor are produced by the navigation computer graphics stage via three output signals. The Red-Green-Blue signals are direct inputs to the board monitor. The audio signals for navigation instructions to the radio are sent via two separate lines.

Scheme 192

MIR (Radio Navigation)

Since a color display is not used for the MIR, the navigation information for the display is sent via a NAV bus. The NAV bus is a single dedicated line between the Mk-3 computer and the MIR. Audio signals for navigation instructions are sent to the radio via two separate lines.

Scheme 193

Speed Signals

A speed signal is provided to the navigation computer for detection of distance traveled and vehicle speed to calculate the vehicles position on the digital map. The input is a processed signal provided by the vehicles DSC control unit.

1. E46: The speed signal used is from the left rear wheel.
2. E38/E39/E52/E53: The speed signal used is from the left front wheel.

Reverse Gear Input

The reverse gear input is used by the navigation computer to distinguish between the vehicle backing up or turning around.

Scheme 194

Scheme 195

1. E38/E39/E52/E53: The reverse input is a high signal produced by the LCM III.
2. E46: The reverse input is a high signal supplied by a splice from the back-up lights.

The Global Positioning System is a satellite based system developed by the US Department of Defense that provides both military and civilian users accurate information about location.

The GPS system uses 24 satellites in six orbits 12,550 miles above the Earth moving at 1.7mi per second. Usually 7 to 10 satellites are in view over any one point on the earth.

The GPS satellites are basically extremely accurate clocks that broadcast a coded signal representing time. The GPS receiver determines it's distance from the satellite by measuring the time it takes between satellite transmission of the signal and reception to the receiver. The receiver does this with at least 2 other satellites and uses the information to determine the vehicles latitude, longitude, and altitude. The accuracy of the system for civilian use is within 100m (300ft).

Scheme 196

The vehicle must have an unobstructed view of the sky to receive the maximum amount of satellite signals. Trees, large buildings and excessive cloud cover can block the reception of the satellites' transmissions.

Scheme 197

The GPS antenna passes the signal to the GPS receiver incorporated in the navigation computer. A CD with map data is loaded in the CD drive of the navigation computer. The navigation computer combines the vehicle position calculated by the GPS with this map data.

The current position of the vehicle can be shown on the on-board monitor by selecting "Emergency" from the main menu.

The driver can enter a destination. The navigation computer calculates a route from the current location to this destination based on selectable criteria (main use of highways, shortest distance, etc.). The calculated route is shown in the route display.

The navigation computer generates the RGB color video signal for all on-board monitor displays. These three signals are sent over separate shielded wires to the on-board monitor.

In the case of the E52 MIR (also referred as radio navigation) which does not have a color display, the visual display data is sent via one wire called the navigation bus. On both systems, color and monochrome display, the audio output from the navigation computer for voice directions is sent over two separate wires.

The driver has the choice of displays that utilize a color map with an icon of the vehicle being traced on the map or the use of arrow indicators and distance data shown on the on-board monitor display. Vehicles equipped with the wide screen board monitor have a split screen option that includes both display methods. The MIR only makes use of the arrows and distance display. With the assistance of voice prompts, the navigation computer indicates how and where to get into the correct lane or turn off.

The navigation computer calculates the distance traveled from the wheel speed signal delivered by the DSC control unit.

The gyro incorporated into the navigation computer housing informs the navigation computer when the vehicle is turning. An alternative route is re-calculated automatically if the driver does not follow the original route instructions.

Once the driver has reached their destination, the navigation computer is ready for another destination input.

Refer to the on-board monitor owners manual for instructions on using the navigation system software.

Replacing The Mk-3 Navigation Computer

When replacing the Mk-3 navigation computer be aware that there are two hardware variants depending on the installation position (vertical or horizontal).

The ignition should be in position 0 during removal and replacement of the computer. After installing, close all doors, hood and trunk. A bus line reset will be carried out within two minutes. Resetting allows the gyro to perform a calibration run. Do not move the car during this reset period.

The coding sequence for the Mk-3 navigation computer has been changed from the previous Mk-2. There is now an additional step (configuration) that must be done before the software can be loaded.

After resetting, a configuration signal is needed to allow the computer to load the correct software for use with a board monitor or MIR. This is performed using the DIS coding program (CD 22.0 onward) and the Navigation System operating software (CD V15.0 onward).

Note. Vehicles using the wide screen BM require CD V16.1 onward. From the DIS/MoDiC Coding/Programming select "1 ZCS Coding" Select the appropriate series (E46,E39,E38,E52,E53) Select "4 Conversion" Select "3 IKE?Kombi" Select "2 language" At the prompt "is the CD ROM present?" select yes, but do not install the operating software CD ROM yet. First select the main language and then an additional language. (i.e. English-spanish) Select the gender of the navigation audio voice. Select "automatic coding-yes" After coding is done the DIS/MoDiC instructs you to follow the instructions on the monitor for the installation of the Navigation System CD ROM. Place the navigation system software in the navigation computer CD drive. IMPORTANT: Do not switch the ignition off during the software loading procedure. Do not use any software for the Mk-3 earlier than CD V15.0. Once loading has been completed, remove the CD and then confirm completion by pressing the rotary push-button on the monitor. Turn off the key for 10 seconds, then turn it back on and conduct a functional check. After this step has been finished, encode the navigation computer using the "Recoding" path in ZCS Coding. The coding process involves coding vehicle specific data: VIN, Model, Telematics data etc.

The software status can be confirmed from the "Set" screen for Mk-3 systems.

Scheme 198

1. 3 = Third generation system Mk-3.
2. 1 = Device variant (1=Color screen, 2= MIR monochrome screen).
3. 20 = Software version of the graphic component (Version 2.0).

After the navigation computer has been successfully programmed and coded the vehicle should be left in an area with a clear view of the sky with the key in KL R for at least 15 minutes to complete the calibration process.

Service Mode

Just as Mk-2, Mk-3 provides an on-screen service mode for diagnosis. The service mode provides five different test screens

1. On-board monitor
2. Navigation/Graphic element
3. GPS
4. Sensor Check
5. Telematics

To Enter The Navigation Service Mode

Scheme 199

Scheme 200

1. Turn the ignition key to position 1 (KL R).
2. From the Menu screen select "SET".
3. Once in the Set screen, press and hold the "MENU" button for 8 seconds.
4. The Service Mode menu will appear on the display.
5. Select from the Service Mode menu for navigation specific tests.

Diagnosis is carried out using Test Modules in the Diagnosis Program as well as on-screen in the Service mode. The Sensor Check display is intended to be used while test driving the vehicle. The following pages contain charts with explanations of the Service Mode display.

Scheme 201

Scheme 202

GPS DIAGNOSIS

GPS STATUS TEXT DISPLAY AND DESCRIPTION

MENU, DISPLAY AND EXPLANATION

Park Distance Control is a safety/convenience system that is an option on the E46. The system is carried over from the E39 and features the ultra-sonic sensors on the rear bumper only.

The sensors detect the close proximity to other objects when maneuvering the vehicle in tight spaces (such as parallel parking or parking in narrow garages spaces).

The driver is warned, through an audible tone (beeping), when the vehicle comes close to another object. As the distance to the object decreases, the beeping frequency increases until a steady tone is produced. As the distance to the object increases, the steady tone will return to a beep and stop when the vehicle moves away from the object.

The PDC is automatically switched ON when the ignition is switched on, however it does not become active until the vehicle is shifted into reverse.

Scheme 203

PDC Components

The PDC consists of the following components

PDC CONTROL MODULE - Mounted in the trunk on the right side above the battery.

The PDC control module activates the ultrasonic sensors mounted in the rear bumper cover. After activation, the module monitors the signals coming back through the sensors. Through this signal, the control module is able to determine the distance to any object close to the bumpers of the vehicle. As the vehicle comes close to an object, the control module will activate the acoustic warning through the right rear audio system speaker.

FOUR ULTRASONIC SENSORS - Mounted in the rear bumper. The sensors are small transmitter/receiver modules that are specifically designed for automotive use. The sensors are limited to the following angles of monitoring

1. 90° on the horizontal plane
2. 60° on the vertical plane

Transmitting Mode

The control module sends a 40 kHz signal to the sensor and each sensor is then activated in a specific sequence (firing order). The ceramic element of the sensor vibrates and produces an ultrasonic sound wave that is sent out from the bumper.

Scheme 204

Receiving Mode

If the sound wave contacts an object, the wave is bounced back to the sensor. The returning wave causes the ceramic element to vibrate creating an electrical signal as feedback to the control module.

The control module determines the distance to the object by the time difference between the sent signal and the received ultrasonic wave signals.

When KL 15 is switched ON, the PDC system is switched "ON", in the standby mode. The system performs a self-check of the ultrasonic sensors and control electronics.

When the vehicle is shifted into reverse, the system is activated and the sensors are activated in the predetermined order.

If an object is detected within the operating range of one the sensors, a signal is sent to the PDC control module and the acoustic warning is generated. At the same time the control module checks the signals from the adjacent sensors to help determine the actual distance to the object.

As the distance to the object decreases, to approximately 1 1/2 feet, the output acoustic frequency increases until a steady tone is generated.

As the distance to the object increases the frequency will decrease until the object is out of the monitoring range of the sensor.

Scheme 205

Scheme 206

See also:
• GPS STATUS TEXT DISPLAY AND DESCRIPTION