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Computers and Control Systems: Locations



Component Locations Overview

Components A to I are not shown in exploded view.
A - "MIL" exhaust emissions warning lamp
- In instrument cluster (Function of lamp)
- See Fig. 2
B - "EPC" warning lamp
- In instrument cluster (Function of lamp)
- See Fig. 3
C - Throttle Position (TP) Sensor -G79- and Sender -2- for accelerator pedal position -G185-
- In footwell at accelerator pedal (integrated into accelerator pedal module)
- See Fig. 5
D - Fuel Pump (FP) Relay -J17-
- In 9-position relay carrier behind driver's storage compartment, relay position 1
- See Fig. 7
E - Brake light switch -F- and Brake Pedal Switch (cruise control/Diesel Direct Fuel Injection) -F47-
- In footwell at pedal bracket next to brake pedal
- See Fig. 6
F - Clutch Vacuum Vent Valve Switch -F36-
- See Fig. 6
G - Motronic Engine Control Module -J220- and relays in plenum chamber electronics box
- Installation locations See Fig. 8 and See Fig. 9
H - Diagnostic connector
- In driver's knee restraint


Component Locations, Overview:






1 - Evaporative Emission (EVAP) canister purge regulator valve -N80-
- See Fig. 4
2 - Mass Air Flow (MAF) sensor -G70- with Intake Air Temperature (IAT) sensor -G42-
3 - Connector console
- Pin assignment
- See Fig. 10
4 - Valve -1- for camshaft adjustment -N205-
- See Fig. 12
5 - Camshaft Position (CMP) sensor -G40-
- Cylinder bank 1
- See Fig. 12
6 - Engine coolant temperature (ECT) sensor -G62-
- At coolant pipe behind cylinder head, bank 1
- See Fig. 12
7 - Fuel supply line
8 - 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-
- See Fig. 12
9 - Oil pressure switch -F1-
- See Fig. 12
10 - Camshaft Position (CMP) Sensor 2 -G163-
- Cylinder bank 2
- See Fig. 12
11 - Connector console
- Pin assignment
- See Fig. 11
12 - Valve -2- for camshaft adjustment -N208-
- See Fig. 12
13 - Engine Speed (RPM) Sensor -G28-
- In transmission housing above ring gear
14 - Ignition coils with output stages
- Cylinder bank 2
15 - 3-pin connector
- For knock sensor 3 -G198-
- For knock sensor 4 -G199-
- See Fig. 13
16 - Secondary Air Injection (AIR) Solenoid Valve -N112-
- See Fig. 13
17 - Intake Manifold Change-Over Valve -N156-
- See Fig. 13
18 - 3-pin connector
- For Knock Sensor (KS) 1 -G61-
- For Knock Sensor (KS) 2 -G66-
- See Fig. 13
19 - Ignition coils with output stages
- Cylinder bank 1
20 - Secondary Air Injection (AIR) Pump Motor -V101-
- Beneath right longitudinal member
- See Fig. 14


Fig. 2 MIL exhaust emissions warning lamp







Emission-specific malfunctions recognized by the engine control module are indicated by activating the exhaust emissions warning lamp.







Exhaust emissions warning lamp (CHECK)


NOTE: Exhaust emissions warning lamp may flash or be constantly lit. DTC memory is always to be checked.


Flashing of exhaust emissions warning lamp
- A malfunction has been detected which will cause the catalytic converter damage in this driving status. In such cases, the vehicle is only to be driven at reduced power (until MIL goes out or lights constantly) and malfunction is to be repaired as quickly as possible.

Constant lighting of exhaust emissions warning lamp
- A malfunction detrimental to emissions has occurred. Check engine control module or automatic transmission DTC memory.
- In the event of engine running problems or a customer complaint without lighting of the exhaust emissions warning lamp, check operation of warning lamp and then check DTC memory, as malfunctions may also have been stored which do not immediately activate the exhaust emissions warning lamp.

Fig. 3 EPC warning lamp







"EPC" is the abbreviation for Electronic Power Control, in other words electronic engine output control (electronic throttle).

When the ignition is turned on, the engine control module switches on the EPC lamp.

After the engine is started the engine control module checks all components relevant to the operation of electronic throttle system.

During the component check, the EPC lamp lights up for approx. 3 seconds. The lamp lights continuously if a malfunction is already established in the course of this check.

If malfunctions in the electronic throttle system are detected during engine operation, the engine control module activates the EPC lamp. At the same time, an entry is made in the engine control module DTC memory.

Fig. 4 Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-







Fig. 5 Installation location of Throttle Position (TP) sensor -G79- Sender -2- for accelerator pedal position -G185-







- Integrated into accelerator pedal module (arrow)

Fig. 6 Installation location of Brake light switch -F-, Brake Pedal Switch (cruise control/Diesel Direct Fuel Injection) -F47- and Clutch Vacuum Vent Valve Switch -F36-







1 - Clutch vacuum vent valve switch -F36-
2 - Brake light switch -F-, Brake Pedal Switch (cruise control/Diesel Direct Fuel Injection) -F47-


NOTE: Switches are only to be installed once, as to ensure a firm fit.


Fig. 7 Installation location of Fuel Pump (FP) Relay -J17-







- Position 1 (arrow) on 9-position relay carrier on left of driver's footwell.

Fig. 8 Installation locations in plenum chamber electronics box







1.1 - Coolant Circulation Pump Relay -J151- (hot countries only)
1.2 - Not used
2 - Secondary Air Injection (AIR) Pump Relay -J299-
3 - Motronic Engine Control Module (ECM) Power Supply Relay -J271-
4 - Relay for automatic transmission
A - Engine electronics fuse S282
B - Secondary air pump fuse S130
C - Not used

Fig. 9 Installation location of engine control module in plenum chamber electronics box







Fig. 10 Assignment of holder for connectors (right side)







1 - 6-pin connector for Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) Heater -Z19- before catalytic converter, bank 1
2 - Connector for starter (terminal 50) and generator
3 - 2-pin connector for camshaft timing control, bank 1
4 - 4-pin connector for 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


Fig. 11 Connector console beneath coolant expansion tank







1 - 4-pin connector for Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 (behind Three Way Catalytic Converter (TWC)) -Z30-, bank 2
2 - 3-pin grey connector for Engine Speed (RPM) Sensor -G28-
3 - 2-pin connector for camshaft timing control, bank 2
4 - 6-pin connector for Heated Oxygen Sensor (HO2S) 2 (-G108) and Oxygen Sensor (O2S) Heater 2 -Z28- before catalytic converter, bank 2

Fig. 12 Rear view







1 - Valve -2- for camshaft adjustment -N208-
2 - Camshaft Position (CMP) Sensor 2 -G163-, cylinder bank 2
3 - Oil pressure switch -F1-
4 - Throttle Valve Control Module -J338-
5 - Engine Coolant Temperature (ECT) Sensor -G62-
6 - Camshaft Position (CMP) Sensor -G40-, cylinder bank 1
7 - Valve -1- for camshaft adjustment -N205-

Fig. 13 Front view







1 - Vacuum unit for intake manifold changeover
2 - Knock Sensor (KS) 1 -G61-
3 - Knock Sensor (KS) 2 -G66-
4 - Intake Manifold Change-Over Valve -N156-
5 - Secondary Air Injection (AIR) Solenoid Valve -N112-
6 - Knock sensor 3 -G198-
7 - Knock sensor 4 -G199-

Fig. 14 Secondary Air Injection (AIR) Pump Motor -V101-







Beneath right longitudinal member

Fig. 15 Leak detection pump (LDP) -V144-







Behind wheel house liner in left rear wheel house.
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