Multiport Fuel Injection (mfi), Generic Scan Tool (3.0l Avk) Audi A4 B6

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 (e.g. 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
4. Always switch ignition off before cleaning engine.

If special testing 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 over 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: Do not work with compressed air if it can be avoided. 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

TECHNICAL DATA

Overview of component locations

Note. The following list 1 to 16 refers to (Scheme 379) and 17 to 37 refers to (Scheme 380).

1. Evaporative Emission (EVAP) canister purge regulator valve -N80- Checking. See «CHECKING EVAPORATIVE EMISSION (EVAP) CANISTER PURGE REGULATOR VALVE -N80»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) .
2. Mass Air Flow (MAF) sensor -G70- with Intake Air Temperature (IAT) sensor -G42- Checking. See «MASS AIR FLOW (MAF) SENSOR -G70-, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
3. Camshaft Position (CMP) Sensor 3 -G300- For exhaust camshaft bank 1 Component location. See «COMPONENT LOCATION OF CAMSHAFT POSITION (CMP) SENSOR -G40- AND CAMSHAFT POSITION (CMP) SENSOR 3 -G300»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-camshaft-position-cmp) . Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk__check-camshaft-position-cmp-sensor) .
4. Camshaft Position (CMP) Sensor -G40- For intake camshaft bank 1 Component location. See «COMPONENT LOCATION OF CAMSHAFT POSITION (CMP) SENSOR -G40- AND CAMSHAFT POSITION (CMP) SENSOR 3 -G300»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-camshaft-position-cmp) . Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk__check-camshaft-position-cmp-sensor) .
5. Brake booster pressure sensor -G294- for vehicles with automatic transmission Component location. See «COMPONENT LOCATION OF BRAKE BOOSTER PRESSURE SENSOR -G294»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
6. Camshaft Position (CMP) Sensor 2 -G163- For intake camshaft bank 2 Component location. See «COMPONENT LOCATION OF CAMSHAFT POSITION (CMP) SENSOR 2 -G163- AND CAMSHAFT POSITION (CMP) SENSOR 4 -G301»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-camshaft-position-cmp) . Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk__check-camshaft-position-cmp-sensor) .
7. Camshaft Position (CMP) Sensor 4 -G301- For exhaust camshaft bank 2 Checking. See «CHECK CAMSHAFT POSITION (CMP) SENSOR»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk__check-camshaft-position-cmp-sensor) .
8. Ignition coils with power output stage, bank 2 Ignition Coil 4 with Power Output Stage -N292- Ignition Coil 5 with Power Output Stage -N323- Ignition Coil 6 with Power Output Stage -N324- Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk) .
9. E-box, plenum chamber Component locations. See «COMPONENT LOCATION OF ENGINE CONTROL MODULE (ECM) IN E-BOX, PLENUM CHAMBER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) and «COMPONENT LOCATIONS IN E-BOX, PLENUM CHAMBER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-locations-in-e-box-plenum-chamber) . Component location of Motronic Engine Control Module (ECM) -J220- Check voltage supply of Engine Control Module (ECM). See «VOLTAGE SUPPLY FOR ENGINE CONTROL MODULE (ECM), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing Engine Control Module (ECM). See «ENGINE CONTROL MODULE (ECM), REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Component location of Motronic Engine Control Module (ECM) voltage supply relay -J271- Check Motronic Engine Control Module (ECM) voltage supply relay -J271-. See «CHECK MOTRONIC ENGINE CONTROL MODULE (ECM) POWER SUPPLY RELAY -J271- AND ACTIVATION»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Component location of Secondary Air Injection (AIR) pump relay -J299- Checking Secondary Air Injection (AIR) Pump Relay -J299-. See «SECONDARY AIR INJECTION (AIR) PUMP RELAY -J299- AND ACTIVATION, CHECKING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) . Component location of fuse S130 for Secondary Air Injection (AIR) pump Component location of Brake booster relay -J569-.
10. Brake System Vacuum Pump -V192- for vehicles with automatic transmission
11. Valve -2- for camshaft adjustment -N208-, intake and Camshaft Adjustment Valve 2 (exhaust) -N319- Bank 2 Checking. See «SOLENOID VALVE FOR CAMSHAFT ADJUSTMENT, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
12. Fuel injectors, bank 2 Cylinder 4 fuel injector -N33- Cylinder 5 Fuel Injector -N83- Cylinder 6 Fuel Injector -N84- Checking. See «CHECK FUEL INJECTORS»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .
13. Fuel injectors, bank 1 Cylinder 1 Fuel Injector -N30- Cylinder 2 fuel injector -N31- Cylinder 3 fuel injector -N32- Checking. See «CHECK FUEL INJECTORS»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .
14. Valve -1- for camshaft adjustment -N205-, intake, Camshaft Adjustment Valve 1 (exhaust) -N318- Bank 1 Checking. See «SOLENOID VALVE FOR CAMSHAFT ADJUSTMENT, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
15. Ignition coils with power output stage, bank 1 Ignition Coil 1 with Power Output Stage -N70- Ignition Coil 2 with Power Output Stage -N127- Ignition Coil 3 with Power Output Stage -N291- Checking. See «IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING»(/audi/a4/b6-2000-2006/remont/ignition-system/#ignitionglow-plug-system-generic-scan-tool-30l-avk) .
16. Secondary Air Injection (AIR) Pump Motor -V101- Checking. See «CHECK VOLTAGE SUPPLY OF THE SECONDARY AIR INJECTION (AIR) PUMP MOTOR»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk__check-voltage-supply-of-the-secondary) .
17. Heated Oxygen Sensor (HO2S) -G39- before catalytic converter with Oxygen Sensor (O2S) Heater -Z19- Bank 1, sensor 1 Constant oxygen sensor Check Oxygen Sensor (O2S) and oxygen sensor control before Three Way Catalytic Converter (TWC). See «CHECK OXYGEN SENSORS AND OXYGEN SENSOR CONTROL BEFORE CATALYTIC CONVERTER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Check oxygen sensor heater for Oxygen Sensor (O2S) before Three Way Catalytic Converter (TWC). See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEFORE THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .
18. Bracket for harness connectors for right side of vehicle Assignment. See «ASSIGNMENT OF BRACKET FOR HARNESS CONNECTORS - RIGHT SIDE OF VEHICLE»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__assignment-of-bracket-for-harness-connectors) .
19. Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G130- with Oxygen Sensor (O2S) Heater 1 -Z29- Bank 1, sensor 2 Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC). See «CHECK OXYGEN SENSOR AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__check-oxygen-sensor-and-oxygen-sensor) . Check oxygen sensor heater for Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC). See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEHIND THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «OXYGEN SENSORS BEHIND CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .
20. Engine Coolant Temperature (ECT) sensor -G62- for Engine Control Module (ECM) At coolant pipe behind cylinder head engine bank 1 with Engine Coolant Temperature (ECT) Sensor -G2- Checking. See «ENGINE COOLANT TEMPERATURE (ECT) SENSOR -G62-, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . If necessary, release pressure in cooling system before removing
21. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__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
22. Secondary Air Injection (AIR) solenoid valve -N112- Checking. See «SECONDARY AIR INJECTION (AIR) SOLENOID VALVE -N112-, CHECKING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .
23. Engine Speed (RPM) sensor -G28- in transmission housing via ring gear Checking. See «ENGINE SPEED (RPM) SENSOR -G28-, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
24. Bracket for harness connectors for left side of vehicle Assignment. See «Assignment of bracket for harness connectors - left side of vehicle»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__assignment-of-bracket-for-harness-connectors) .
25. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-throttle-position-tp-sensor) . Checking. See «THROTTLE POSITION (TP) SENSOR, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) . 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 LINKAGE, SERVICING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk__accelerator-linkage-servicing) .
26. Fuel Pump (FP) Relay -J17- Component location. See «COMPONENT LOCATIONS FUEL PUMP (FP) RELAY -J17»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-locations-fuel-pump-fp-relay) . Checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
27. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-brake-light-switch) .
28. Clutch vacuum vent valve switch -F36- Component location. See «COMPONENT LOCATION OF BRAKE LIGHT SWITCH -F- AND BRAKE PEDAL SWITCH -F47-, CLUTCH VACUUM VENT VALVE SWITCH -F36»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-brake-light-switch) . Checking. See «CLUTCH VACUUM VENT VALVE SWITCH -F36-, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk)
29. Instrument cluster With Malfunction Indicator Lamp (MIL) -K83-. See «MALFUNCTION LAMP FOR ON BOARD DIAGNOSTIC (OBD)/MALFUNCTION INDICATOR LAMP (MIL) -K83- IN INSTRUMENT CLUSTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__malfunction-lamp-for-on-board-diagnostic) . With Electronic Power Control (EPC) Warning Lamp -K132-. See «ELECTRONIC POWER CONTROL (EPC) WARNING LAMP -K132- IN INSTRUMENT CLUSTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__electronic-power-control-epc-warning-lamp) .
30. Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- with Oxygen Sensor (O2S) Heater 2 -Z30- Bank 2, sensor 2 Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC). See «CHECK OXYGEN SENSOR AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__check-oxygen-sensor-and-oxygen-sensor) . Check oxygen sensor heater for Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC). See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEHIND THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «OXYGEN SENSORS BEHIND CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .
31. Heated Oxygen Sensor (HO2S) 2 -G108- before catalytic converter with Oxygen Sensor (O2S) 2 Heater -Z28- Bank 2, sensor 1 Constant oxygen sensor Check Oxygen Sensor (O2S) and oxygen sensor control before Three Way Catalytic Converter (TWC). See «CHECK OXYGEN SENSORS AND OXYGEN SENSOR CONTROL BEFORE CATALYTIC CONVERTER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Check oxygen sensor heater for Oxygen Sensor (O2S) before Three Way Catalytic Converter (TWC). See «Oxygen sensor heater for oxygen sensors before Three Way Catalytic Converter (TWC), checking»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Removing and installing. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .
32. Fuel pressure regulator Checking. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
33. Knock Sensor (KS) 2 -G66- Bank 2 below intake manifold
34. Intake manifold change-over valve -N156- Component location. See «COMPONENT LOCATION OF INTAKE MANIFOLD CHANGE-OVER VALVE -N156»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__component-location-of-intake-manifold-change-over) .
35. Knock Sensor (KS) 1 -G61- Bank 1 below intake manifold
36. Ground connection on the engine bracket, right
37. not installed

Scheme 379

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 locations Fuel Pump (FP) Relay -J17

1. located at position 1 -arrow- of relay carrier in driver's footwell, left

Component location of Brake light switch -F- and Brake pedal switch -F47-, Clutch vacuum vent valve switch -F36

1. Clutch vacuum vent valve switch -F36
2. Brake light switch -F-, Brake pedal switch -F47

Scheme 380

Removing and installing switch

See appropriate Clutches article in Transmission. See BRAKELIGHT SWITCH

Scheme 381

Component locations in E-box, plenum chamber

1. 1.1 - Coolant Circulation Pump Relay -J151- (only hot countries)
2. 1.2 - Not assigned
3. 2 - Motronic Engine Control Module (ECM) voltage supply relay -J271
4. 3 - Secondary Air Injection (AIR) pump relay -J299

1. Engine Electronics Fuse S282
2. Fuse S130 for Secondary Air Injection (AIR) pump
3. Not assigned

Scheme 382

Assignment of bracket for harness connectors - right side of vehicle

1. 6-pin harness connector, black for Heated Oxygen Sensor (HO2S) -G39- before catalytic converter and Oxygen Sensor (O2S) Heater -Z19- (bank 1 sensor 1)
2. 3-pin harness connector, blue for Knock Sensor (KS) 1 -G61
3. 4-pin harness connector, green for Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC) -G130- and Oxygen Sensor (O2S) Heater 1 -Z29- (bank 1 sensor 2)
4. 3-pin harness connector, black for terminal 50

Assignment of bracket for harness connectors - left side of vehicle

1. 4-pin harness connector, brown for Oxygen Sensor (O2S) 2 behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- (bank 2 sensor 2)
2. 3-pin harness connector, gray for Engine Speed (RPM) sensor -G28
3. 3-pin harness connector, blue for Knock Sensor (KS) 2 -G66
4. 6-pin harness connector, black for Heated Oxygen Sensor (HO2S) 2 -G108- before catalytic converter and Oxygen Sensor (O2S) 2 Heater -Z28- (bank 2 sensor 1)

Note. To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom on reservoir must be disconnected, and the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.

Scheme 383

Scheme 384

Component location of Intake Manifold Change-Over Valve -N156

1. clipped to vacuum element

Component location of Camshaft Position (CMP) Sensor -G40- and Camshaft Position (CMP) Sensor 3 -G300

1. At cylinder head bank 1 (right side), rear - Electrical harness connector for Camshaft Position (CMP) Sensor 3 -G300- - Electrical harness connector for Camshaft Position (CMP) Sensor -G40

Component location of Camshaft Position (CMP) Sensor 2 -G163- and Camshaft Position (CMP) Sensor 4 -G301

1. At cylinder head bank 2 (left side), rear - Electrical harness connector for Camshaft Position (CMP) Sensor 2 -G163- - Electrical harness connector for Camshaft Position (CMP) Sensor 4 -G301

Air filter - component overview

Note. The following list refers to (Scheme 393).

1. to Secondary Air Injection (AIR) Pump Motor -V101
2. O-ring Always replace
3. Sheet-metal screw
4. Air duct
5. Air duct to lock carrier
6. Expanding clip
7. Seal
8. Cover
9. Mass Air Flow (MAF) sensor -G70
10. Connection hose
11. Sheet-metal screw
12. Upper part of air filter housing
13. Filter element
14. Lower part of air filter housing

Fuel rail with fuel injectors - component overview

Note. The following list refers to (Scheme 394).

1. Retaining clip Make sure clip is correctly seated on fuel injector and fuel rail
2. O-ring Removing and installing. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) . Always replace Coat with clean engine oil
3. Fuel injector Removing and installing. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .
4. O-ring Removing and installing. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) . Always replace Coat with clean engine oil
5. Fuel return line
6. Fuel supply line Union nut, tighten to 25 N.m
7. 10 N.m
8. Fuel distributor
9. 10 N.m
10. Retaining clip Check for secure fitting
11. O-Rings Always replace Coat with clean engine oil
12. Fuel pressure regulator
13. Vacuum hose

Fuel injectors, removing and installing

1. Remove rear engine cover (arrows).
2. Remove bolts for holding plate for solenoid valves (arrows).
3. Remove front engine cover (arrows).
4. Disconnect harness connector at Intake Manifold Change-Over Valve -N156- -Item 1-.
5. Disconnect all harness connectors at fuel injectors, to do this disengage harness connectors at the bottom -arrow
6. Disconnect vacuum hose -3- from fuel pressure regulator.
7. Unscrew fuel distributor from intake manifold (arrows). NOTE: Fuel supply line -2- and fuel return line -1- must be disconnected before replacing fuel distributor. CAUTION: Fuel system is under pressure! Before opening system, place rags around the connection. Then release pressure by carefully loosening connection.
8. Remove fuel distributor with injectors from intake manifold simultaneously upward and set aside in rear of engine compartment on a clean cloth.
9. Disengage retaining clip and remove fuel injector.

Installing

Installation is reverse of removal, noting the following

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

Tightening torque

TIGHTENING TORQUE (FUEL INJECTORS)

Solenoid valves for camshaft adjustment - component overview

Note. The following list refers to (Scheme 401).

1. Seals
2. Housing for camshaft adjustment valves
3. O-Rings between solenoid valve housing and solenoid valves
4. O-Rings
5. O-Rings
6. 4 N.m
7. Camshaft adjustment valve - intake side Cylinder bank 1 (right): Valve -1- for camshaft adjustment -N205- Cylinder bank 2 (left): Valve -2- for camshaft adjustment -N208
8. Gasket Replace if damaged
9. Connector adapter Must be replaced after disconnecting from camshaft adjustment valves Carefully press onto harness connectors of camshaft adjustment valves until they engage Electrical harness connector. See «ELECTRICAL HARNESS CONNECTOR ON CONNECTOR ADAPTER FOR SOLENOID VALVES FOR CAMSHAFT ADJUSTMENT»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
10. 4 N.m
11. Camshaft adjustment valve - exhaust side Cylinder bank 1 (right): Camshaft Adjustment Valve 1 (exhaust) -N318- Cylinder bank 2 (left): Camshaft Adjustment Valve 2 (exhaust) -N319
12. Gasket
13. 10 N.m

Scheme 385

1. Front on cylinder head, cylinder bank 2 (left side) -arrow

Recommended special tools and equipment

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

Test requirements

1. Fuse for oxygen sensor heating OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
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.

Procedure

1. Disconnect electrical 6-pin harness connector -1- from Heated Oxygen Sensor (HO2S) -G39- (before catalytic converter) and Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1).
2. Disconnect electrical 6-pin harness connector -4- from Heated Oxygen Sensor (HO2S) -G108- (before catalytic converter) and Oxygen Sensor (O2S) 2 Heater 2 -Z28- (bank 2, sensor 1).

Note. To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom of the reservoir must be disconnected, and the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.

Scheme 386

Scheme 387

1. Connect multimeter between terminal 3 and 4 for resistance measurement. Specified value at room temperature: 2.5 ... 10 ohm If specified value is not obtained
2. Replace respective oxygen sensor before catalytic converter. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .

If specified value is obtained

Checking voltage supply

1. Connect multimeter between terminal 3 and 4 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 HARNESS CONNECTOR TERMINAL 3 SPECIFICATIONS (HEATER FOR HO2S BEFORE THREE WAY CATALYTIC CONVERTER) Harness connector Terminal Measure to 3 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 3 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 388

1. Connect multimeter for voltage measurement as follows: HO2S HARNESS CONNECTOR TERMINAL 4 SPECIFICATIONS (HEATER FOR HO2S BEFORE THREE WAY CATALYTIC CONVERTER) Harness connector Terminal Measure to 4 B+
2. Operate starter briefly. Specified value: approx. battery voltage
3. Switch ignition off.

If specified value is not obtained

Scheme 389

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; 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): HARNESS CONNECTOR TERMINAL 4, SOCKET 5 SPECIFICATIONS (OXYGEN SENSOR (O2S) HEATER -Z19- BANK 1, SENSOR 1) Harness connector Terminal Test box Socket 4 5 Oxygen Sensor (O2S) Heater 2 -Z28- (bank 2, sensor 1): HARNESS CONNECTOR TERMINAL 4, SOCKET 4 SPECIFICATIONS (OXYGEN SENSOR (O2S) HEATER 2 -Z28- BANK 2, SENSOR 1) Harness connector Terminal Test box Socket 4 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).

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

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

1. Fuse for oxygen sensor heating OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
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 -3- 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 -1- from Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- (bank 2, sensor 2).

Note. To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom on reservoir must be disconnected, and the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.

Scheme 390

Checking internal resistance

1. Connect multimeter between terminal 1 and 2 for resistance measurement. Specified value at room temperature: 6.4 ... 47.5 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/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .

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 HARNESS CONNECTOR TERMINAL 1 SPECIFICATIONS (HEATER FOR HO2S BEHIND THREE WAY CATALYTIC CONVERTER) 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 391

1. Connect multimeter for voltage measurement as follows: HO2S HARNESS CONNECTOR TERMINAL 2 SPECIFICATIONS (HEATER FOR HO2S BEHIND THREE WAY CATALYTIC CONVERTER) 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 392

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; 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: HO2S HARNESS CONNECTOR TERMINAL 2, SOCKET 63 SPECIFICATIONS (HEATER FOR HO2S BEHIND THREE WAY CATALYTIC CONVERTER) Harness connector Terminal Test box Socket 2 63 Oxygen Sensor (O2S) heater -Z30- bank 2 behind catalytic converter: HO2S HARNESS CONNECTOR TERMINAL 2, SOCKET 6 SPECIFICATIONS (HEATER FOR HO2S BEHIND THREE WAY CATALYTIC CONVERTER) 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).

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

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

Component location. See OVERVIEW OF COMPONENT LOCATIONS .

1. Fuse for Mass Air Flow (MAF) sensor OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
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. See «MODE 1: CHECK MEASURING VALUES»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-1-check-measuring-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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measuring values."
4. Select the desired measuring value "PID 16: Air flow quantity at Mass Air Flow (MAF) sensor". Specified value: 1.0 ... 5.0 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
2. Check voltage supply and wire connections. See «CHECKING VOLTAGE SUPPLY»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .

If the specified value is exceeded

1. Eliminate engine load via additional equipment (A/C system/power-assisted steering/Generator).
2. Check voltage supply and wire connections. See «CHECKING VOLTAGE SUPPLY»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .

Scheme 393

1. Remove cover -1- in engine compartment (right side).
2. Disconnect harness connector -arrow- at Mass Air Flow (MAF) sensor.
3. Connect multimeter for voltage measurement as follows. HARNESS CONNECTOR TERMINAL 2 SPECIFICATIONS (MASS AIR FLOW SENSOR) Harness connector Terminal Measure to 2 Engine Ground (GND)
4. Operate starter briefly. Specified value: approx. battery voltage
5. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__checking-wire-connections) .
2. Connect multimeter between terminal 1 and 3 of harness connector for voltage measurement.
3. Switch ignition on. Specified value: about 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 394

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL SPECIFICATIONS (MASS AIR FLOW SENSOR) Harness connector Terminal Test box Socket 1 53 3 27 4 29 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 Mass Air Flow (MAF) sensor -G70-. See item 2 .

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . 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 multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
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. See «MODE 1: CHECK MEASURING VALUES»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-1-check-measuring-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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Switch ignition on.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measuring values."
4. Select the desired measuring value "PID 17: Throttle valve position (absolute)." Specified value: 12 ... 16 %
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: 84 ... 88 %
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . 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/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) .
3. Disconnect electrical harness connector at throttle valve control module.

Scheme 395

1. Switch ignition on.
2. Connect multimeter for voltage measurement as follows: HARNESS CONNECTOR TERMINAL 2 + GROUND & 2 + 6 SPECIFICATIONS (THROTTLE VALVE CONTROL MODULE) Harness connector Terminal Specified value 2 + Ground (GND) about 5 V 2 + 6 about 5 V
3. Switch ignition off.

If specified values are not obtained

Scheme 396

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINALS 1 TO 6 SPECIFICATIONS (THROTTLE VALVE CONTROL MODULE) 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 the throttle valve control module. See item 21 .
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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

1. VAG1526A 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. Disconnect electrical harness connector -2- from Engine Speed (RPM) sensor.

Note. To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom on reservoir must be disconnected, the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.

Scheme 397

Scheme 398

1. Connect multimeter between terminal 2 and 3 for resistance measurement. Specified value: 730 ...1000 ohm 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. See item 23 .

If specified value is obtained

Scheme 399

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. See item 23 .

If specified value is obtained

Scheme 400

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINALS 1, 2, 3 & SOCKETS 108, 90, 82 SPECIFICATIONS (ENGINE SPEED SENSOR) 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 detected

1. Replace 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

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

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

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
2. Ignition switched off.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measuring 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.

If indications do not resemble description

Scheme 401

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
3. Check the following wire connection for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 5, SOCKET 26 SPECIFICATIONS (INTAKE AIR TEMPERATURE SENSOR) Harness connector Terminal Test box Socket 5 26 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-. See item 2 .

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

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

Component location. See OVERVIEW OF COMPONENT LOCATIONS .

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
2. Engine cold

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Switch ignition on.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measuring 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.

1. 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. If indications do not resemble description

1. Disconnect harness connector -2- at Engine Coolant Temperature (ECT) Sensor -G2-/-G62-.
2. Connect multimeter between terminal C and D of sensor for resistance measurement. Range A displays resistance values for the temperature range of 0...50 °C, range B displays resistance values for the temperature range of 50...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-. See item 20 .

If specified value is obtained

Scheme 402

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINALS 3, 4 & SOCKETS 108, 93 SPECIFICATIONS (ENGINE COOLANT TEMPERATURE SENSOR) 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).

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

1. VAG1526A multimeter
2. VAG 1527 B Voltage Tester
3. VAG1594A connector test kit
4. VAG1598/31 test box

1. Fuse for valve for camshaft adjustment OK. See appropriate System Wiring Diagrams article.
2. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
3. Ignition switched off. NOTE: Voltage for camshaft adjustment solenoid valves is supplied via Motronic ECM power supply relay.

Cylinder bank 2 (left)

1. Remove cover -1- in engine compartment (left side).
2. Remove coolant reservoir (arrow)
3. Remove line from Engine Coolant Level (ECL) Warning Switch -F66- and lay coolant reservoir to side. NOTE: Coolant hoses -1- to -3- remain connected.

Cylinder bank 1 (right)

1. Remove cover -1- in engine compartment (right side).
2. Remove bolts (arrows).
3. Detach Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- -1- at air guide.
4. Remove air guide -2-.
5. Remove air filter housing (arrows).

Continuation for both sides

1. Disconnect harness connector (arrow) from connector-adapter. NOTE: Illustration depicts cylinder bank 2 (left).

Valve for camshaft adjustment (intake)

1. Connect multimeter between terminal 1 and 2 for resistance measurement. Specified value: 7.4 ... 8.2 ohm

Valve for camshaft adjustment (exhaust)

1. Connect multimeter between terminal 2 and 3 for resistance measurement. Specified value: 12.8 ... 14.2 ohm

All

If specified value is not obtained

1. Replace the respective solenoid valve for camshaft adjustment. See «SOLENOID VALVE FOR CAMSHAFT ADJUSTMENT, CHECKING»(ref-197058-S08942079552005101100000) .

If specified value is obtained

Scheme 403

1. Connect e.g. V.A.G 1527 B voltage tester as follows: HARNESS CONNECTOR TERMINAL 2 SPECIFICATIONS (SOLENOID VALVE FOR CAMSHAFT ADJUSTMENT) Harness connector Terminal Measure to 2 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 2 of harness connector via fuse to Motronic Engine Control Module (ECM) Power Supply Relay -J271- 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 404

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL SPECIFICATIONS (SOLENOID VALVE FOR CAMSHAFT ADJUSTMENT) Valve for camshaft adjustment Harness connector Terminal Test box Socket Intake bank 1, Valve -1- for camshaft adjustment -N205- 1 115 Intake bank 2, Valve -2- for camshaft adjustment -N208- 1 120 Exhaust bank 1, Camshaft Adjustment Valve 1 (exhaust) -N318- 1 22 Exhaust bank 2, Camshaft Adjustment Valve 2 (exhaust) -N319- 1 18 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).

If no malfunctions are detected

1. Replace mechanical camshaft adjuster. See «CAMSHAFTS AND CAMSHAFT ADJUSTERS, REMOVING AND INSTALLING»(ref-197058-S08890454852005101100000) .

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

1. VAG1526A multimeter
2. VAG 1527 B Voltage Tester
3. VAG1594A connector test kit
4. VAG1598/31 test box

Note. This signal helps prevent excessive RPM oscillations and tip-in shocks when clutch is disengaged and is required for the cruise control system.

1. Ignition switched off.

Scheme 405

1. Remove driver-side storage compartment: For Cabriolet models, see «DRIVER-SIDE STORAGE COMPARTMENT (WITH AND WITHOUT KNEE BOLSTER), ASSEMBLY OVERVIEW»(ref-197209-S29048734852005101300000) . For models other than Cabriolet, see «DRIVER-SIDE STORAGE COMPARTMENT (WITH AND WITHOUT KNEE BOLSTER), ASSEMBLY OVERVIEW»(/audi/a4/b6-2000-2006/remont/mirrors/#interior-equipment-except-cabriolet__driver-side-storage-compartment-with-and-without) .
2. Disconnect harness connector at Clutch Pedal Position (CPP) switch -1-.
3. Connect multimeter between terminal 2 and 3 for resistance measurement. Specified value: approx. 0 ohm
4. Depress clutch pedal. Specified value: INFINITY ohm (no continuity)

If specified value is not obtained

1. Replace Clutch Pedal Position (CPP) switch. See appropriate Clutches article in Transmission.

If specified values are obtained

Scheme 406

1. Connect e.g. V.A.G 1527 B voltage tester as follows: HARNESS CONNECTOR TERMINAL 3 SPECIFICATIONS (CLUTCH VACUUM VENT VALVE SWITCH) Harness connector Terminal Measure to 3 Chassis Ground (GND)
2. Switch ignition on. LED must light up.
3. Switch ignition off.

If LED does not light up

1. Check the wire connection for open circuit. Specified value: Wire resistance max 1.5 ohm
2. If necessary, repair wire connection.

If LED lights up

Scheme 407

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connection for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 2, SOCKET 39 SPECIFICATIONS (CLUTCH VACUUM VENT VALVE SWITCH) Harness connector Terminal Test box Socket 2 39 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.

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

1. VAG1526A 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.

Function test of Fuel Pump (FP) relay

1. Remove driver-side storage compartment: For Cabriolet models, see «DRIVER-SIDE STORAGE COMPARTMENT (WITH AND WITHOUT KNEE BOLSTER), ASSEMBLY OVERVIEW»(ref-197209-S29048734852005101300000) . For models other than Cabriolet, see «DRIVER-SIDE STORAGE COMPARTMENT (WITH AND WITHOUT KNEE BOLSTER), ASSEMBLY OVERVIEW»(/audi/a4/b6-2000-2006/remont/mirrors/#interior-equipment-except-cabriolet__driver-side-storage-compartment-with-and-without) .
2. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; 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 (position 1, at 9-pin relay carrier in driver's footwell, left) must trigger and Fuel Pump (FP) must run.

1. If Fuel Pump (FP) runs: Check voltage supply of Fuel Pump (FP) relay. See «CHECK VOLTAGE SUPPLY OF FUEL PUMP (FP) RELAY»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . Checking activation of Fuel Pump (FP) relay. See «CHECKING ACTIVATION OF FUEL PUMP (FP) RELAY»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
2. If Fuel Pump (FP) does not run: 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__check-voltage-supply-for-fuel-pump) .

Scheme 408

1. Remove Fuel Pump (FP) relay.
2. Connect multimeter for voltage measurement as follows. HARNESS CONNECTOR TERMINAL 1 SPECIFICATIONS (FUEL PUMP RELAY) 9-pin relay carrier in driver's footwell, left side, position 1 Terminal Measure to 1 Chassis Ground (GND) Specified value: approx. battery voltage
3. Connect multimeter for voltage measurement as follows: HARNESS CONNECTOR TERMINAL 3 SPECIFICATIONS (FUEL PUMP RELAY) 9-pin relay carrier in driver's footwell, left side, position 1 Terminal Measure to 3 Chassis Ground (GND)
4. Switch ignition on. Specified value: approx. battery voltage
5. 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

If specified values are obtained

Scheme 409

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
4. Check the following wire connection for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 5, SOCKET 65 SPECIFICATIONS (FUEL PUMP RELAY) 9-pin relay carrier in driver's footwell, left side, position 1 Terminal Test box Socket 5 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-. or
2. Replace 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. 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
2. Delivery quantity of Fuel Pump (FP) OK; check. For front wheel drive see «SUPPLY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) . For all wheel drive see «SUPPLY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) .
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 rear engine cover (arrows).

Checking system pressure

1. Open fuel filler flap briefly (pressure release).
2. Connect e.g. V.A.G 1318 pressure gauge in fuel supply line using adapters 1318/6 and 1318/7.
3. Disconnect vacuum hose 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.
4. Start engine and let run at idle.
5. Measure fuel pressure. Specified value: 3.8 ... 4.2 bar
6. 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

1. Check vacuum hose for tears and damage.
2. Check vacuum hose at intake manifold for throughput by disconnecting hose from fuel pressure regulator and blowing into it. 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 with a cold engine: approx. 2.2 bar Specified value with the engine at operating temperature: approx. 3.0 bar NOTE: Pressure increase for an engine at operating temperature limited by the fuel expansion is normal.
2. Start engine and let run at idle.
3. Wait until pressure has dropped, 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.

The following malfunctions are possible if the pressure does not drop

1. There is a leak in the threaded 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). For front wheel drive see «SUPPLY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) . For all wheel drive see «SUPPLY QUANTITY OF FUEL PUMP (FP), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) . NOTE: Pressure gauge displays the pressure behind the stopcock "intake manifold side" after the stopcock is closed (in direction of fuel injector, fuel pressure regulator). If the pressure drops in front of the stopcock (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. Threaded connections of pressure gauge behind stopcock are not properly sealed. NOTE: Close stopcock for removing the pressure gauge, loosen threaded connection at VAG1318/7 adapter and let excess fuel escape into catch reservoir by opening stopcock.

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

1. VAG1526A 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 See appropriate System Wiring Diagrams article.
2. Fuel Pump (FP) Relay OK; checking. See «FUEL PUMP (FP) RELAY -J17- AND ACTIVATION, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
3. Ignition switched off. NOTE: Voltage is supplied to the fuel injectors via the Fuel Pump (FP) relay.

1. Remove front engine cover (arrows).
2. Disconnect harness connector at Intake Manifold Change-Over Valve -N156- -Item 1-.

Continuation for both cylinder banks

1. Disconnect all harness connectors at fuel injectors of the respective cylinder bank. To do this, disengage harness connectors at the bottom -arrow

1. Connect multimeter at valve for resistance measurement. Specified value: 11 ... 13 ohms (at room temperature)

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

If specified value is not obtained

1. Replace fuel injector. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .

If specified value is obtained

Scheme 410

1. Connect e.g. V.A.G 1527 B voltage tester as follows: HARNESS CONNECTOR TERMINAL 1 SPECIFICATIONS (CHECKING FUEL INJECTORS) 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

Scheme 411

1. Internal resistance of valve OK 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. Operate starter briefly (engine can also start).
2. 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 412

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 2, SOCKETS 96, 112, 88, 97, 113, 89 SPECIFICATIONS (CHECKING FUEL INJECTORS) Cylinder Fuel injector harness connector Terminal Test box Socket 1 2 96 2 2 112 3 2 88 4 2 97 5 2 113 6 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).

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
2. Ignition switched off.

Test sequence

1. Remove fuel distributor including fuel injectors from intake manifold. See «FUEL INJECTORS, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; 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...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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .

Scheme 413

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 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: 90 ... 125 ml
8. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__fuel-injectors-removing-and-installing) .
9. Repeat test at fuel injectors of second cylinder row.
10. 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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . NOTE: Also check spray pattern when checking injection quantity. Spray pattern must be the same for all injectors
11. Install fuel injectors together with fuel distributor. See «INSTALLING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . 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 and performance 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. See «MODE 1: CHECK MEASURING VALUES»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-1-check-measuring-values) .
2. Ignition switched off.

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Start engine and let run at idle.
3. In diagnostic function "33 - OBD", select "Mode 1: Checking measuring 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 measuring values: DIAGNOSTIC CHART: PID 06, 08, 12 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) 700 to 800 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 eliminate the error.

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

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

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
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 °. See «MODE 1: CHECK MEASURING VALUES»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-1-check-measuring-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 the Vehicle Diagnostic, Testing and Information System VAS 5051 or the Vehicle Diagnostic and Information System VAS 5052 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
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

DIAGNOSTIC CHART: TEST-ID 129-132

1. 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
2. Check primary voltage. See «CHECKING PRIMARY VOLTAGE»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__checking-primary-voltage) .
3. Test oxygen sensor heater before catalytic converter. See «OXYGEN SENSOR HEATER FOR OXYGEN SENSORS BEFORE THREE WAY CATALYTIC CONVERTER (TWC), CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
4. Check intake system for leaks (false air). See «CHECKING INTAKE SYSTEM FOR LEAKS (UNMETERED AIR)»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
5. Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC). See «CHECK OXYGEN SENSOR AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__check-oxygen-sensor-and-oxygen-sensor) .
6. Check fuel pressure regulator and residual pressure. See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
7. Check fuel injectors. See «CHECK FUEL INJECTORS»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
8. Check Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-. See «CHECKING EVAPORATIVE EMISSION (EVAP) CANISTER PURGE REGULATOR VALVE -N80»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) .
9. Check Fuel Pump (FP). For front wheel drive see «FUEL PUMP (FP), ELECTRICAL TESTING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) . For all wheel drive see «FUEL PUMP (FP), ELECTRICAL TESTING»(/audi/a4/b6-2000-2006/remont/fuel-system/#fuel-supply-generic-scan-tool-30l-avk) .
10. Check exhaust system for proper seal. See «CHECK EXHAUST SYSTEM FOR PROPER SEAL»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk__check-exhaust-system-for-proper-seal) .
11. Check Secondary Air Injection (AIR) system for proper seal. See «CHECKING SECONDARY AIR SYSTEM FOR PROPER SEAL»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk__checking-secondary-air-system-for-proper) .
12. Check vacuum lines for proper seal.

Checking primary voltage

1. Disconnect electrical 6-pin harness connector -1- from Heated Oxygen Sensor (HO2S) -G39- (before catalytic converter) and Oxygen Sensor (O2S) Heater -Z19- (bank 1, sensor 1).
2. Disconnect electrical 6-pin harness connector -4- from Heated Oxygen Sensor (HO2S) 2 -G108- (before catalytic converter) and Oxygen Sensor (O2S) Heater 2 -Z28- (bank 2, sensor 1).

Note. To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom on reservoir must be disconnected, and the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.

Scheme 414

1. Connect multimeter between terminal 1 and 5 for voltage measurement.
2. Switch ignition on. Specified value: 0.400 ... 0.500 V
3. Switch ignition off. If specified value is not obtained
4. Check oxygen sensor wires. See «CHECK OXYGEN SENSOR WIRES FOR HEATED OXYGEN SENSOR (HO2S) -G39- (BANK 1, SENSOR 1)»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) and «CHECK OXYGEN SENSOR WIRES FOR HEATED OXYGEN SENSOR (HO2S) 2 -G108- (BANK 2, SENSOR 1)»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . If specified value is obtained
5. Replace respective oxygen sensor before catalytic converter. See «OXYGEN SENSORS BEFORE CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .

Scheme 415

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 1, 2, 5, 6 & SOCKETS 70, 71, 51, 52 SPECIFICATIONS (BANK 1, SENSOR 1) Harness connector Terminal Test box Socket 1 70 2 71 5 51 6 52 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
5. Replace Engine Control Module (ECM).

Scheme 416

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
2. Check the following wire connections for open circuit. HARNESS CONNECTOR TERMINALS 1, 2, 5, 6 & SOCKETS 13, 14, 12, 15 SPECIFICATIONS (BANK 2, SENSOR 1) Harness connector Terminal Test box Socket 1 13 2 14 5 12 6 15 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
5. Replace 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) . End diagnosis and switch ignition off.

Check oxygen sensor and oxygen sensor control behind catalytic converter

Note. The oxygen sensor before catalytic converter (bank 1, sensor 1 or bank 2, sensor 1) holds the value at Lambda = 1. If this oxygen sensor is damaged, e.g. due to dirt or overheating, the controlled 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 multimeter
2. VAG1594A connector test kit
3. VAG1598/31 test box

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
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. See «MODE 1: CHECK MEASURING VALUES»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-1-check-measuring-values) .

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
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 the Vehicle Diagnostic, Testing and Information System VAS 5051 or the Vehicle Diagnostic and Information System VAS 5052 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.

Scheme 417

1. Select the desired output of oxygen sensor signals according to the following table. DIAGNOSTIC CHART TEST-ID 07, 08 Test-ID Diagnostic text Specified value min. max. 07: Minimum voltage at sensor for test cycle Bank 1, sensor 2 Bank 2, sensor 2 0.000 V 0.625 V 08: Maximum voltage at sensor for test cycle Bank 1, sensor 2 Bank 2, sensor 2 0.625 V 1.000 V
2. 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
3. Road test vehicle in order to free oxygen sensors of possible residue and repeat test.

If specified values are not obtained again

Scheme 418

1. Disconnect electrical 4-pin harness connector -3- 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 -1- from Oxygen Sensor (O2S) 2 Behind Three Way Catalytic Converter (TWC) -G131- and Oxygen Sensor (O2S) Heater 2 -Z30- (bank 2, sensor 2). NOTE: To reach the harness connectors, the left cover in engine compartment must be removed, the line to Engine Coolant Level (ECL) Warning Switch at bottom on reservoir must be disconnected, and the bolt -arrow- of the coolant reservoir must be unscrewed and set aside. Coolant hoses -1- to -3- remain connected.
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
6. Check oxygen sensor wires. See «CHECK OXYGEN SENSOR WIRES FOR OXYGEN SENSOR (O2S) BEHIND THREE WAY CATALYTIC CONVERTER (TWC) -G130- (BANK 1, SENSOR 2)»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) and «CHECK OXYGEN SENSOR WIRES FOR OXYGEN SENSOR (O2S) 2 BEHIND THREE WAY CATALYTIC CONVERTER (TWC) -G131- (BANK 2, SENSOR 2)»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) . If specified value is obtained
7. Replace respective oxygen sensor behind catalytic converter. See «OXYGEN SENSORS BEHIND CATALYTIC CONVERTER, REMOVING AND INSTALLING»(/audi/a4/b6-2000-2006/remont/exhaust/#exhaust-system-emission-controls-generic-scan-tool-30l-avk) .

Scheme 419

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINALS 3, 4 & SOCKETS 68, 69 SPECIFICATIONS 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
5. Replace Engine Control Module (ECM).

Scheme 420

1. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Check the following wire connections for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINALS 3, 4 & SOCKETS 10, 11 SPECIFICATIONS 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
5. Replace 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .

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

1. Fuses for engine electronics OK See appropriate System Wiring Diagrams article.
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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
2. Switch ignition on. NOTE: The positive voltage supply for the Engine Control Module (ECM) travels via terminal 3 (terminal 15) and terminal 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: TEST BOX SOCKET 1, 2, 62 SPECIFICATIONS (ECM) 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: TEST BOX SOCKET 3 SPECIFICATIONS (ECM) 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
8. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm
9. Connect multimeter for voltage measurement as follows: TEST BOX SOCKET 121 SPECIFICATIONS (ECM) Test box Socket Measure to 121 (1) Engine Ground (GND) (1) The Motronic Engine Control Module (ECM) power supply relay -J271- continues to direct current to terminal 121 of the Engine Control Module (ECM) for up to 15 minutes after ignition is switched off.
10. Switch ignition on. Specified value: approx. battery voltage
11. Switch ignition off. If specified value is not obtained
12. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm
13. If necessary, repair wire connection.
14. Check Motronic Engine Control Module (ECM) power supply relay -J271-. See «CHECK MOTRONIC ENGINE CONTROL MODULE (ECM) POWER SUPPLY RELAY - J271- AND ACTIVATION»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .

Special Tools and Equipment

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

Note. The Motronic Engine Control Module (ECM) power supply relay -J271- supplies voltage to the ignition coils with power output stages and the Engine Control Module (ECM) at pin 121.

1. Ignition switched off.

Scheme 421

Scheme 422

1. Remove cover -1- in engine compartment (left side).
2. Remove coolant reservoir (arrow)
3. Disconnect electrical wiring to Engine Coolant Level (ECL) Warning Switch -F66- at bottom of reservoir.
4. Lay aside coolant reservoir with connected coolant hoses -1- to -3-.
5. Remove bolts (arrows) on cylinder head at left.
6. Disconnect 4-pin harness connectors -4- to -6- at ignition coils. NOTE: For further testing, connect the multimeter to harness connector in place of an ignition coil.
7. Connect multimeter for voltage measurement as follows. HARNESS CONNECTOR TERMINAL 1 SPECIFICATIONS Harness connector Terminal Measure to 1 Engine Ground (GND)
8. Switch ignition on. Specified value: approx. battery voltage
9. Switch ignition off. If specified value is not obtained
10. Remove rubber seal for plenum chamber cover.
11. Remove plenum chamber cover -1- toward front (arrows).
12. Pry off both covers -3- using a screwdriver.
13. Loosen hex-nuts -4- by several turns.
14. Loosen wiper arm -2- from wiper axle by lightly tilting.
15. Remove hex nuts completely and remove wiper arms.
16. Disconnect securing clips -1- and remove cowl grill -5-.
17. Remove cover for E-box, plenum chamber (arrows).
18. Pry off Engine Control Module (ECM) retaining bracket (arrows) using a screwdriver and set control module aside.
19. If installed, unclip Transmission Control Module (TCM) retaining bracket and set control module aside.
20. Disconnect power supply relay -2-.
21. Check the following wire connection for open circuit according to wiring diagram: HARNESS CONNECTOR TERMINAL 1 SPECIFICATIONS (ECM) Relay carrier in E-box, plenum chamber, position 2 Terminal Harness connector at ignition coils Terminal 8 1 Specified value: Wire resistance max 1.5 ohm
22. If necessary, repair wire connection. If no malfunctions are found in wires
23. Check voltage supply of Motronic Engine Control Module (ECM) power supply relay -J271-. See «CHECKING VOLTAGE SUPPLY»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .
24. Check activation of Motronic Engine Control Module (ECM) power supply relay -J271-. See «CHECKING ACTIVATION»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk) .

Scheme 423

1. Connect multimeter for voltage measurement as follows. POSITION 2 TERMINAL 1 & 2 SPECIFICATIONS (ECM) Relay carrier in E-box, plenum chamber, position 2 Terminal Measure to 1 Engine Ground (GND) 2 Engine Ground (GND) Specified value: approx. battery voltage If specified value is not obtained
2. Check wire connections for open circuit according to wiring diagram: Specified value: Wire resistance max 1.5 ohm

Scheme 424

Scheme 425

1. Connect multimeter for voltage measurement as follows. POSITION 2 TERMINAL 4 SPECIFICATIONS (ECM) Relay carrier in E-box, plenum chamber, position 2 Terminal Measure to 4 B+
2. Switch ignition on. Specified value: approx. battery voltage
3. Switch ignition off. If specified value is not obtained
4. Connect test box to wiring harness of Engine Control Module (ECM). See «TEST BOX, CONNECTING FOR WIRING AND COMPONENT TEST»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; ECM is not connected.
5. Check the following wire connection for open circuit according to wiring diagram: POSITION 2 TERMINAL 4, SOCKET 23 SPECIFICATIONS (ECM) Relay carrier in E-box, plenum chamber, position 2 Terminal Test box Socket 4 23 Specified value: Wire resistance max 1.5 ohm
6. Also check the wire for short circuit to B+ and Ground (GND). Specified value: INFINITY ohm (no continuity)
7. If necessary, repair wire connection. If no malfunctions are detected
8. Replace Motronic Engine Control Module (ECM) power supply relay -J271-.

Removing

1. Pull off rubber seal of plenum chamber cover in direction of arrow.
2. Remove cover -1- toward front.
3. Pry off both covers -3- using a screwdriver.
4. Loosen hex-nuts -4- by several turns.
5. Loosen wiper arm -2- from wiper axle by lightly tilting.
6. Remove hex nuts completely and remove wiper arms.
7. Disconnect securing clips -1- and remove cowl grill -5-.
8. Remove cover for E-box, plenum chamber (arrows).
9. Using a screwdriver, pry off retaining bracket (arrow).
10. 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.
11. 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. If DTC memory was erased, generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .

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.

1. Procedure to replace Engine Control Module (ECM): See «ENGINE CONTROL MODULE (ECM) (WITHOUT METAL ANTI-THEFT HOUSING), REPLACING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-30l-avk__engine-control-module-ecm-without-metal) or «ENGINE CONTROL MODULE (ECM) (WITH METAL ANTI-THEFT HOUSING), REPLACING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-30l-avk__engine-control-module-ecm-with-metal) .

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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. If necessary, erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. If DTC memory was erased, generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .

1. Function and display of speedometer OK. Troubleshooting

1. Connect diagnostic tester. See «CONNECT DIAGNOSTIC TESTER»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .
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 the 2nd person observe the indication on the display. DIAGNOSTIC CHART: PID 13 PID Diagnostic text Specified value 13 Vehicle speed approx. vehicle speed
6. End diagnosis and switch ignition off. If no speed is displayed
7. Check terminal resistance for CAN-Bus. See «TERMINAL RESISTANCE FOR CAN-BUS, CHECKING»(/audi/a4/b6-2000-2006/remont/fuel-system/#multiport-fuel-injection-mfi-generic-scan-tool-30l-avk__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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-3-check-dtc-memory) .
2. Erase DTC memory. See «MODE 4: RESET/ERASE DIAGNOSTIC DATA»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk__mode-4-reseterase-diagnostic-data) .
3. Generate readiness code. See «READINESS CODE, GENERATING»(/audi/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) .

Terminal resistance for CAN-Bus, checking

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

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 databus 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 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/a4/b6-2000-2006/remont/testing-diagnostics/#engine-controls-on-board-diagnostic-obd-generic-scan-tool-30l-avk) ; wiring harness is not connected.
2. Check the central terminal resistor in the Engine Control Module (ECM)
3. Connect multimeter between terminal 58 and 60 of test box for resistance measurement. Specified value: 60 ...72 ohm If the specification is exceeded or not met
4. Replace Engine Control Module (ECM). If specified value is obtained
5. Disconnect test box from Engine Control Module (ECM).
6. Connect test box to control module wiring harness.
7. Check CAN data bus wires for shorts among one another
8. Connect multimeter between terminal 58 and 60 of test box for resistance measurement. Specified value: INFINITY ohm (no continuity)
9. If necessary, repair wire connection according to wiring diagram.

See also:
• READINESS CODE, GENERATING
• BATTERY DISCONNECT PRECAUTIONS
• CHECKING EVAPORATIVE EMISSION (EVAP) CANISTER PURGE REGULATOR VALVE -N80
• CHECK CAMSHAFT POSITION (CMP) SENSOR
• IGNITION COILS WITH POWER OUTPUT STAGES, CHECKING
• SECONDARY AIR INJECTION (AIR) PUMP RELAY -J299- AND ACTIVATION, CHECKING
• CHECK VOLTAGE SUPPLY OF THE SECONDARY AIR INJECTION (AIR) PUMP MOTOR
• ACCELERATOR LINKAGE, SERVICING
• 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
• BRAKELIGHT SWITCH
• MODE 3: CHECK DTC MEMORY
• MODE 4: RESET/ERASE DIAGNOSTIC DATA
• MODE 1: CHECK MEASURING VALUES
• DRIVER-SIDE STORAGE COMPARTMENT (WITH AND WITHOUT KNEE BOLSTER), ASSEMBLY OVERVIEW
• CHECK EXHAUST SYSTEM FOR PROPER SEAL
• CHECKING SECONDARY AIR SYSTEM FOR PROPER SEAL
• ENGINE CONTROL MODULE (ECM) (WITHOUT METAL ANTI-THEFT HOUSING), REPLACING
• ENGINE CONTROL MODULE (ECM) (WITH METAL ANTI-THEFT HOUSING), REPLACING
• MASS AIR FLOW (MAF) SENSOR -G70-, CHECKING
• COMPONENT LOCATION OF CAMSHAFT POSITION (CMP) SENSOR -G40- AND CAMSHAFT POSITION (CMP) SENSOR 3 -G300
• COMPONENT LOCATIONS IN E-BOX, PLENUM CHAMBER
• FUEL INJECTORS, REMOVING AND INSTALLING
• ASSIGNMENT OF BRACKET FOR HARNESS CONNECTORS - RIGHT SIDE OF VEHICLE
• CHECK OXYGEN SENSOR AND OXYGEN SENSOR CONTROL BEHIND CATALYTIC CONVERTER
• THROTTLE VALVE CONTROL MODULE -J338-, CHECKING
• COMPONENT LOCATION, THROTTLE POSITION (TP) SENSOR -G79- AND SENDER 2 FOR ACCELERATOR PEDAL POSITION -G185
• COMPONENT LOCATIONS FUEL PUMP (FP) RELAY -J17
• COMPONENT LOCATION OF BRAKE LIGHT SWITCH -F- AND BRAKE PEDAL SWITCH -F47-, CLUTCH VACUUM VENT VALVE SWITCH -F36
• COMPONENT LOCATION OF INTAKE MANIFOLD CHANGE-OVER VALVE -N156
• OVERVIEW OF COMPONENT LOCATIONS
• CHECKING WIRE CONNECTIONS
• CHECK VOLTAGE SUPPLY FOR FUEL PUMP (FP) AND COMPONENTS
• INSTALLING
• CHECKING PRIMARY VOLTAGE
• Safety precautions
• TERMINAL RESISTANCE FOR CAN-BUS, CHECKING