2.0l - Multiport Fuel Injection - Engine Code(s): Aeg (hatchback) Volkswagen New Beetle A4

MOTRONIC FUEL INJECTION SYSTEM, SERVICING

The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.

For all Motronic fuel injection system component locations. Refer to Fuel Injection System .

For all Motronic fuel injection system removal/installation procedures and torque specifications. Refer to Fuel Injection System .

Note. Manufacturers special tools as well as common tools that contain a manufacturer specific part number may be referenced in the test procedure illustrations showing the tool use or installation. If the manufacturer specific tool is not being used, an equivalent aftermarket tool may be installed in the same manner as the manufacturers special tool.

SAFETY PRECAUTIONS

To reduce the risk of personal injury and/or damage to the fuel injection and ignition system. Note the following

1. Always switch off ignition before disconnecting or connecting lines of the fuel injection and ignition system, including test leads.
2. During some of the tests, a Diagnostic Trouble Code (DTC) may be recognized and stored by the control module. At the end of all tests and repairs, the DTC memory should be checked and, if necessary, erased. After erasing the DTC memory, a readiness code must be generated for the engine control module.
3. Always switch ignition off before cleaning engine.

Observe the following if test and measuring instruments are required during a test drive

CLEAN WORKING CONDITIONS

Even minor contaminations can lead to malfunctions in the fuel injection system. When working on the fuel supply/injection system, pay careful attention to the following Clean Working Conditions

1. Thoroughly clean all unions and adjacent areas with engine or brake cleaner and dry before disconnecting.
2. Plug open lines and connections immediately with appropriate protective caps.
3. Place removed parts on a clean surface and cover. Use lint-free cloths.
4. Install clean components: Remove replacement parts immediately prior to installation. Do not use parts that have been stored unpacked (e.g. in tool boxes etc.).
5. When the system is open: Do not work with compressed air. Do not move vehicle unless absolutely necessary.
6. Separated electrical connectors: Protect from dirt and moisture. Make sure connections are dry when reconnecting.

TECHNICAL DATA

COMPONENTS, CHECKING

The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.

OXYGEN SENSOR HEATER Z19, CHECKING

Note. When servicing terminals in harness connector of Oxygen Sensor (O2S) Heater -Z19-, use only gold-plated terminals.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Oxygen Sensor (O2S) Heater -Z19- fuse OK.
2. Battery voltage at least 12.5 V.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Checking internal resistance

Disconnect the Oxygen Sensor (O2S) Heater -Z19- electrical harness connector -1-.

Scheme 115

Using a multimeter, check the Oxygen Sensor (O2S) Heater -Z19- terminals 1&2 for an open circuit.

Specified value: 2.5 to 10.0 ohms (at approx. 20° C)

If the specification was not obtained

Replace the Oxygen Sensor (O2S) Heater -Z19-.

If the specification is obtained

Checking voltage supply

Using a multimeter, check the Oxygen Sensor (O2S) Heater -Z19- electrical harness connector terminal 1 to engine ground (GND) for voltage.

Scheme 116

Specified value: 12.5 V, Battery voltage.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, lose or broken terminals.

If necessary, repair the faulty wiring connection.

If the specification was obtained

Checking Ground (GND) activation

If the manufacturers test box is being used. Perform the following step.

Install the test box.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a multimeter, check the Oxygen Sensor (O2S) Heater -Z19- electrical harness connector terminal 2 to the Motronic Engine Control Module (ECM) -J220- electrical harness connector terminal 27 for an open circuit.

Specified value: 1.5 ohms max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, lose or broken terminals.

If necessary, repair the faulty wiring connection.

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

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

OXYGEN SENSOR HEATER Z28, CHECKING

Note. Vehicle must be raised before electrical harness connector for the Oxygen Sensor (O2S) 2 Heater -Z28- is accessible. When servicing terminals in harness connector of Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z29-, use only gold-plated terminals.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z28- fuse OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Checking internal resistance

Disconnect the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z28- electrical harness connector -1-.

Scheme 117

Using a multimeter, check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z29- electrical harness connector terminals 1 to 2 for resistance.

Specified value: 1.0 to 20.0 ohms (at approx. 20° C)

If the specification was not obtained

Replace the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z29-.

If the specification was obtained

Checking voltage supply

Using a multimeter, check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z28- electrical harness connector terminal 1 to Engine Ground (GND).

Turn key on

Specified value: 12.5 V, Battery voltage.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, lose or broken terminals.

If necessary, repair the faulty wiring connection.

Turn key off.

If the specification was obtained

Checking Ground (GND) activation

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a multimeter, check the Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater -Z28- electrical harness connector terminal 2 to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminal 28 for an open circuit according to the wiring diagram.

Specified value: 1.5 ohms max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, lose or broken terminals.

If necessary, repair the faulty wiring connection.

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

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

MASS AIR FLOW SENSOR G70, CHECKING

Note. Use only gold-plated terminals when servicing terminals in harness connector of Mass Air Flow (MAF) Sensor -G70-.

Note. Intake Air Temperature (IAT) Sensor -G42- is an integral part of Mass Air Flow (MAF) Sensor -G70- replacement of Mass Air Flow sensor results in IAT replacement also.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Mass Air Flow (MAF) Sensor -G70- fuse OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Coolant Temperature at least 80° C.
8. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Function test

Connect the scan tool.

Start engine and let it run at idle.

Using the scan tool, Check the air flow quantity of the Mass Air Flow (MAF) Sensor -G70- at idle

End diagnosis and switch ignition off.

If specified value is obtained, but DTC memory has a DTC concerning Mass Air Flow (MAF) Sensor -G70

Check voltage supply of Mass Air Flow (MAF) Sensor -G70- MASS AIR FLOW SENSOR G70, CHECKING .

If specified value was not obtained

Check the Mass Air Flow (MAF) Sensor -G70- electrical circuit MASS AIR FLOW SENSOR G70, CHECKING .

Checking voltage supply

Disconnect the Mass Air Flow (MAF) Sensor -G70- electrical harness connector -arrow-.

Scheme 118

Start the engine and let it run at idle.

Using a multimeter, check the Mass Air Flow (MAF) Sensor -G70- electrical harness connector terminal 2 to engine Ground (GND).

Scheme 119

Specified value: battery voltage.

Switch the ignition off.

If specified value was not obtained

Check the Mass Air Flow (MAF) Sensor -G70- electrical harness connector terminal 2 to the Fuse 43 (on fuse panel B) -S243- for an open circuit.

Specified value: 1.5 ohms max.

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

Checking Ground (GND)

Using a multimeter, check the Mass Air Flow (MAF) Sensor -G70- electrical harness connector terminal 1 to engine Ground (GND) for resistance.

Specified value: 1.5 ohms max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

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

Checking electrical circuit

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a multimeter, check the Mass Air Flow (MAF) Sensor -G70- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit.

Specified value: 1.5 ohms max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

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

Replace Mass Air Flow (MAF) Sensor -G70-. Refer to Fuel Injection System

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

INTAKE AIR TEMPERATURE SENSOR G42, CHECKING

Note. Use only gold-plated terminals when servicing terminals in the electrical harness connector of the Intake Air Temperature (IAT) Sensor -G42-.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.
3. Cool spray (commercially available).

Test requirements

1. The Motronic Engine Control Module (ECM) - J220- fuses OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Connect the scan tool.

Switch the ignition on.

Using the scan tool, check the intake air temperature

If the specified value is not obtained

Continue the test according to the following table

If the specified values are obtained

Note. Intake Air Temperature (IAT) Sensor -G42- is an integral part of Mass Air Flow (MAF) Sensor -G70- and requires replacement of Mass Air Flow sensor also.

Remove the Intake Air Temperature (IAT) Sensor -G42-. Refer to Fuel Injection System .

Spray the Intake Air Temperature (IAT) Sensor -G42- with a commercially available cool spray while observing the temperature value on the scan tool.

The temperature value must decrease.

End diagnosis and switch the ignition off.

If the intake air temperature does not decrease

Replace the Intake Air Temperature (IAT) Sensor -G42-. Refer to Fuel Injection System .

If the intake air temperature does decrease

Checking internal resistance

Disconnect the Intake Air Temperature (IAT) Sensor -G42- electrical harness connector -arrow-.

Using a multimeter, check the Intake Air Temperature (IAT) Sensor -G42- terminals 1 to 3 for resistance.

Scheme 120

Use the chart below for the specified values

1. Area A: Resistance values 0 to 50° C.
2. Area B: Resistance values 50 to 100° C.

Specified values

Scheme 121

Read-out examples

1. Range A, 30° C equals a resistance of 1.5 to 2.0 kohms
2. Range B, 80° C equals a resistance of 275 to 375ohms

If any of the specified values are not obtained

Replace the Intake Air Temperature (IAT) Sensor -G42-. Refer to Fuel Injection System .

Testing if display approx. -40° C or approx. -46° C

Disconnect the Intake Air Temperature (IAT) Sensor -G42- electrical harness connector -arrow-.

Using a jumper wire, connect the Intake Air Temperature (IAT) Sensor -G42- electrical harness connector terminals 1 to 2.

Check the value indicated on the scan tool display.

If indication jumps to approx. 140° C

End diagnosis and switch ignition off.

Replace the Intake Air Temperature (IAT) Sensor -G42-. Refer to Fuel Injection System .

If indication remains at approx. -40° C or -46° C

Testing if display approx. 140° C

Disconnect the Intake Air Temperature (IAT) Sensor -G42- electrical harness connector -arrow-.

If indication jumps to approx. -40° C or -46° C

End diagnosis and switch ignition off.

Replace the Intake Air Temperature (IAT) Sensor -G42-. Refer to Fuel Injection System .

If the indication remains at approx. 140° C

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Intake Air Temperature (IAT) Sensor -G42- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit according to the wiring diagram.

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

If necessary, repair the faulty wiring connection.

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If no malfunction is detected in the wiring

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

THROTTLE VALVE CONTROL MODULE J338, CHECKING

Note. Use only gold-plated terminals when servicing terminals in harness connector of Throttle Valve Control Module -J338-.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Motronic Engine Control Module (ECM) - J220- fuses OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Throttle valve must not be damaged or dirty.
8. Coolant Temperature at least 80° C.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Function

Throttle valve operation occurs by an electric motor (Throttle Position (TP) Actuator -V60-) in the Throttle Valve Control Module - J338-. It is operated by the Motronic Engine Control Module (ECM) -J220- and the Throttle Position (TP) Sensor -G69- /Throttle Position (TP) Sensor -G88-.

The Throttle Valve Control Module -J338- is made up of the following components

1. Throttle Position (TP) Actuator -V60
2. Throttle Position (TP) Sensor -G69
3. Throttle Position (TP) Sensor -G88

The Throttle Valve Control Module -J338- cannot be serviced separately and must be serviced as a unit.

Function test

Connect the scan tool.

Switch ignition on.

Using the scan tool, check the throttle valve position (absolute) at idle stop

Slowly depress the accelerator pedal to the Wide Open Throttle (WOT) stop while observing the percentage display. The percentage display must increase uniformly.

Using the scan tool, check the throttle valve position (absolute) at Wide Open Throttle (WOT) stop

End diagnosis and switch ignition off.

If the specified values are not obtained

Remove the Throttle Valve Control Module -J338 - far enough so that the electrical connector terminals are reached.

Disconnect the Throttle Valve Control Module -J338- electrical harness connector -arrow-.

Scheme 122

Checking resistance

Using a multimeter, check the Throttle Position (TP) Actuator -V60- at the Throttle Valve Control Module -J338- terminals 1 to 2 for resistance.

Scheme 123

Specified value: 1.0 to 5.0 ohms (at 20° C)

If the specification was not obtained

Replace the Throttle Valve Control Module - J338-.

If the specification was obtained

Check the voltage supply of the Throttle Valve Control Module -J338- to the Motronic Engine Control Module (ECM) -J220-.

THROTTLE POSITION SENSOR G69 AND THROTTLE POSITION SENSOR G88, CHECKING .

Checking voltage supply and wiring

Switch the ignition on.

Using a Multimeter --, check the Throttle Position (TP) Actuator -V60- at the Throttle Valve Control Module -J338- electrical harness connector terminals 4 to 8 for voltage.

Specified value: at least 4.5 V

Switch the ignition off.

If the specification was not obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Throttle Position (TP) Actuator -V60- at Throttle Valve Control Module -J338- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit according to the wiring diagram.

Scheme 124

Specified value: 1.5 ohms max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

If necessary, repair the faulty wiring connection.

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If no malfunction is detected in the wiring and if the voltage supply was not OK

Replace the Throttle Valve Control Module -J338-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

POSITIVE CRANKCASE VENTILATION HEATING ELEMENT N79, CHECKING

Note. Use only gold-plated terminals when servicing terminals in the electrical harness connector of Positive Crankcase Ventilation (PCV) Heating Element -N79-.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

The Motronic Engine Control Module (ECM) - J220- fuses OK.

The Fuel Pump (FP) Relay -J17- OK.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

1. Battery voltage at least 12.5 volts.
2. All electrical consumers such as, lights and rear window defroster, switched off.
3. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
4. A/C switched off.
5. Ground (GND) connections between engine/transmission/chassis OK.
6. Ignition switched off.
7. Engine warm.

Checking internal resistance

Disconnect the Positive Crankcase Ventilation (PCV) Heating Element -N79- electrical harness connector -2-.

Scheme 125

Using a multimeter, check the Positive Crankcase Ventilation (PCV) Heating Element -N79- terminals 1 to 2 for resistance.

Scheme 126

Specified value: 25 to 35 ohms (at approx. 20° C)

If the specified value was not obtained

Replace the Positive Crankcase Ventilation (PCV) Heating Element -N79-.

If the specified value was obtained

Checking voltage

Switch the ignition on.

Using a multimeter --, check the Positive Crankcase Ventilation (PCV) Heating Element -N79- electrical connector terminal 2 to Ground (GND) for voltage.

Scheme 127

Specified value: battery voltage.

Switch the ignition off.

If the specified value was not obtained

Check the wiring from the Positive Crankcase Ventilation (PCV) Heating Element -N79- electrical connector terminal 2 to the Fuse 32 -- for a short circuit to Ground (GND), or an open circuit.

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the wiring connection.

If no malfunctions are found in the wiring

Checking Ground (GND)

Using a multimeter --, check the Positive Crankcase Ventilation (PCV) Heating Element -N79- electrical connector terminal 1 to Ground (GND) for resistance.

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring

Replace the Positive Crankcase Ventilation (PCV) Heating Element -N79-.

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

ENGINE COOLANT TEMPERATURE SENSOR G62, CHECKING

Note. Use only gold-plated terminals when servicing terminals in the electrical harness connector of Engine Coolant Temperature (ECT) Sensor -G62-.

Special tools and workshop equipment required

1. Multimeter.
2. jumper wire.
3. Wiring diagram.

Test requirements

1. The Motronic Engine Control Module (ECM) - J220- fuses OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.
8. Engine cold.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Connect the scan tool.

Switch the ignition on.

Using the scan tool, check the coolant temperature

If the specified value is not obtained

Continue test according to the following table

If the specified value was obtained

Start the engine and let it run at idle.

The temperature value must increase uniformly 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.

Replace the Engine Coolant Temperature (ECT) Sensor - G62-. Refer to Cooling System Component Overview, Engine Side .

Checking internal resistance

Disconnect the Engine Coolant Temperature (ECT) Sensor -G62- electrical harness connector -arrow-.

Scheme 128

Using a multimeter, check the Engine Coolant Temperature (ECT) Sensor -G62- terminals 3 to 4 for resistance.

Scheme 129

Use the chart below for the specified values

1. Area A: Resistance values 0 to 50° C.
2. Area B: Resistance values 50 to 100° C.

Specified values

1. Range A, 30° C equals a resistance of 1.5 to 2.0 kohms
2. Range B, 80° C equals a resistance of 275 to 375ohms

If any of the specified values was not obtained

Replace the Engine Coolant Temperature (ECT) Sensor - G62-. Refer to Cooling System Component Overview, Engine Side .

Testing if display is approx. - 40.0° C

Disconnect the Engine Coolant Temperature (ECT) Sensor -G62- electrical harness connector -arrow-.

Using a jumper wire, connect the Engine Coolant Temperature (ECT) Sensor -G62- electrical harness connector terminals 3 to 4.

Scheme 130

Check the value indicated on the scan tool display.

If the value jumps to approx. 140.0° C

End diagnosis and switch the ignition off.

Replace the Engine Coolant Temperature (ECT) Sensor - G62-. Refer to Cooling System Component Overview, Engine Side .

If indication remains at approx. -40.0° C

Testing if display approx. 140.0° C

Disconnect the Engine Coolant Temperature (ECT) Sensor -G62- electrical harness connector -arrow-.

If indication jumps to approx. -40.0° C

End diagnosis and switch ignition off.

Replace the Engine Coolant Temperature (ECT) Sensor - G62-. Refer to Cooling System Component Overview, Engine Side .

If indication remains at approx. 140.0° C

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Engine Coolant Temperature (ECT) Sensor - G62- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit according to the wiring diagram.

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

ENGINE SPEED SENSOR G28, CHECKING

Note. Use only gold-plated terminals when servicing terminals in the electrical harness connector of the Engine Speed (RPM) Sensor -G28-.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Motronic Engine Control Module (ECM) - J220- fuses OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

The Engine Speed (RPM) Sensor -G28- detects RPM and reference marks. Without an engine speed signal, the engine will not start. If the engine speed signal fails while the engine is running, the engine will stop immediately.

Function test

Connect the scan tool.

Switch the ignition on.

Using the scan tool, check the engine speed

End diagnosis and switch ignition off.

If the specified value was not obtained

Checking internal resistance

Disconnect the gray Engine Speed (RPM) Sensor -G28- electrical harness connector -arrow-.

Scheme 131

Using a multimeter, check the Engine Speed (RPM) Sensor -G28- terminals 2 to 3 for resistance.

Scheme 132

Specified value: 0.7 to 1000 kOhm

Check Engine Speed (RPM) Sensor -G28- terminals 1 to 2 and 1 to 3 for short circuits.

Specified value: infinity (infinity)

If any of the specified values are not obtained

Replace the Engine Speed (RPM) Sensor -G28-. Refer to CYLINDER BLOCK AND COMPONENTS OVERVIEW .

If the specified values are obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Engine Speed (RPM) Sensor -G28- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit.

Scheme 133

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring

Remove the Engine Speed (RPM) Sensor -G28- and check the sensor wheel for proper seating, damage and run-out. Refer to CRANKSHAFT ASSEMBLY OVERVIEW . Replace if damaged.

If the sensor wheel is OK

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

FUEL INJECTORS N30, N31, N32, N33, CHECKING

The following test procedure is used to diagnose all fuel injectors.

Special tools and workshop equipment required

1. Multimeter.
2. Diode test lamp (12V).
3. Wiring diagram.

Test requirements

1. The Fuel Injectors -N30, N31, N32, N33- fuses OK.
2. The Engine Speed (RPM) Sensor -G28- OK. «ENGINE SPEED SENSOR G28, CHECKING»(/volkswagen/new-beetle/a4-1997-2005/remont/fuel-system/#20l-multiport-fuel-injection-engine-codes-aeg-hatchback__engine-speed-sensor-g28-checking) .
3. Battery voltage at least 12.5 volts.
4. All electrical consumers such as, lights and rear window defroster, switched off.
5. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
6. A/C switched off.
7. Ground (GND) connections between engine/transmission/chassis OK.
8. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Observe Safety Precautions.

Observe Clean Working Conditions.

Procedure

Remove the engine cover with air filter.

Disconnect the Fuel Injector -- electrical harness connectors from Fuel Injectors -N30, N31, N32, N33-.

Checking internal resistance

Using a multimeter, check the Fuel Injector -- electrical terminals 1 to 2 for resistance.

Scheme 134

Specified value: 14.0 to 20.0 ohms (at approx. 20° C)

If the specified value was not obtained

Replace the malfunctioning Fuel Injector --. Refer to Fuel Injection System .

If the specified value was obtained

Checking activation

Connect a diode test lamp (12V) to the electrical harness connector terminals 1 and 2 of the Fuel Injector -- to be tested.

Scheme 135

Operate the starter and test the activation of the Fuel Injector --.

LED should flicker.

Switch the ignition off.

If LED does not flicker

Checking voltage

Connect a diode test lamp (12V) to the electrical harness connector terminal 1 of the Fuel Injector -- to be tested and ground.

Ignition on

Operate the starter and test the activation of the Fuel Injector --.

LED should flicker.

Ignition off.

If diode test lamp does not light up, check wire between 2 pin electrical harness (pin 1) and respective fuse 32 for an open circuit.

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Fuel Injector -- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit.

Scheme 136

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring

Install the engine cover with air filter.

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

FUNCTION TESTS

The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.

HEATED OXYGEN SENSOR G39, CHECKING

Note. Use only gold-plated terminals when servicing terminals in the electrical harness connector of the Heated Oxygen Sensor (HO2S) -G39-.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Heated Oxygen Sensor (HO2S) -G39- fuse OK.
2. The Oxygen Sensor (O2S) Heater -Z19- before catalytic converter OK. Refer to «OXYGEN SENSOR HEATER Z19, CHECKING»(/volkswagen/new-beetle/a4-1997-2005/remont/fuel-system/#20l-multiport-fuel-injection-engine-codes-aeg-hatchback__oxygen-sensor-heater-z19-checking) .
3. Battery voltage at least 12.5 volts.
4. All electrical consumers such as, lights and rear window defroster, switched off.
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Exhaust system between catalytic converter and cylinder head properly sealed.
8. Coolant Temperature at least 80° C.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Perform a function test. Refer to DIAGNOSTIC MODE 05 - READ OXYGEN SENSOR MONITORING TEST RESULTS .

If the specified values are not obtained

Checking primary voltage

Disconnect the Heated Oxygen Sensor (HO2S) -G39- electrical harness connector -1-.

Using a multimeter, check the Heated Oxygen Sensor (HO2S) -G39- electrical harness connector terminals 3 to 4 for voltage.

Switch ignition on.

Specified value: 0.400 to 0.500 Volts

Switch the ignition off.

If the specified value was obtained

Replace the Heated Oxygen Sensor (HO2S) -G39-. Refer to EXHAUST MANIFOLD, FRONT EXHAUST PIPE AND ATTACHMENTS ASSEMBLY OVERVIEW [for engine(s) AEG] .

If the specified value was not obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Heated Oxygen Sensor (HO2S) -G39- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit.

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

OXYGEN SENSOR HEATER AFTER CATALYTIC CONVERTER G108, CHECKING

Note. When servicing terminals in the electrical harness connector of the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G108-, use only gold-plated terminals.

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G108- fuse Ok.
2. Oxygen Sensor (O2S) 1 (behind Three Way Catalytic Converter (TWC)) Heater - Z28- OK.
3. Battery voltage at least 12.5 volts.
4. All electrical consumers such as, lights and rear window defroster, switched off.
5. Vehicles with automatic transmission, selector lever in position "P" or "N".
6. A/C switched off.
7. Ground (GND) connections between engine/transmission/chassis OK.
8. Exhaust system between catalytic converter and cylinder head properly sealed.
9. Coolant Temperature at least 80° C.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Perform a function test. Refer to DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS .

If the specified values are not obtained

Procedure

Disconnect the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector -1-.

Checking primary voltage

Switch the ignition on.

Using a multimeter, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) -G108- electrical harness connector terminals 3 to 4 for voltage.

Scheme 137

Specified value: 0.400 to 0.500 Volts

Switch the ignition off.

If the specified value was obtained

Replace the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) - G108-. Refer to EXHAUST MANIFOLD, FRONT EXHAUST PIPE AND ATTACHMENTS ASSEMBLY OVERVIEW [for engine(s) AEG] .

If the specified value was not obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter --, check the Oxygen Sensor (O2S) Behind Three Way Catalytic Converter (TWC) - G108- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminals for an open circuit according to the wiring diagram.

Specified value: 1.5 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Install the protective cover -arrows-.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

MOTRONIC ENGINE CONTROL MODULE J220

The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.

FUNCTION

Motronic Engine Control Module (ECM) -J220- regulates fuel injection, Throttle Valve Control Module -J338-, oxygen sensor regulation, ignition, knock control, Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-, engine speed limitation through fuel injectors or Fuel Pump (FP) Relay -J17- as well as On Board Diagnostic (OBD).

VOLTAGE SUPPLY, CHECKING

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Motronic Engine Control Module (ECM) - J220- fuses OK.
2. Battery voltage at least 12.5 volts.
3. All electrical consumers such as, lights and rear window defroster, switched off.
4. Vehicles with automatic transmission, selector lever in position "P" or "N".
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Remove the Fuel Pump (FP) Relay -J17-.

Checking voltage

Using a Multimeter, check the Fuel Pump (FP) Relay -J17- socket 17 to Ground (GND).

Specified value: battery voltage.

If the specified value was not obtained

Check the wiring connections from the Battery to the Fuel Pump (FP) Relay -J17- socket 17 for an open circuit or a short circuit.

Check the wiring connections for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If the specified value was obtained

Switch the ignition on.

Using a Multimeter, check the Fuel Pump (FP) Relay -J17- socket 23 to Ground (GND).

Specified value: battery voltage.

Switch the ignition off.

If the specified value was obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter, check the Fuel Pump (FP) Relay -J17- socket 19 to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 terminal 1 for resistance.

Specified value: 2.0 ohms Max.

If the specification was not obtained

Check the wiring for a short circuit to each other, Battery (+), or Ground (GND).

Check the electrical harness connector for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring

Replace the Fuel Pump (FP) Relay -J17-.

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

MOTRONIC ENGINE CONTROL MODULE J220, REPLACING

Removing

Special tools and workshop equipment required

1. Heat gun, screwdriver, locking pliers.

Note. When the Motronic Engine Control Module (ECM) -J220- electrical harness connectors are disconnected, the adaptation values are erased and the DTC memory content remains intact.

Work procedure

Check the identification of the previous Motronic Engine Control Module (ECM) -J220- as follows

Connect the scan tool.

Switch the ignition on.

Using the scan tool, select "Vehicle information".

Select " Calibration Identification" in vehicle information.

The electronic control module identification number will be displayed, e.g.: 06A906032NA 4983

Record the electronic control module identification number.

End diagnosis and switch the ignition off.

Procedure

Switch the ignition on.

Actuate the touch-wipe function to allow the wipers to move to the service position.

Scheme 138

Remove the wiper arms caps -arrows-.

Scheme 139

Loosen the wiper arm nuts -arrows- several turns.

Scheme 140

Loosen the wiper arms from the wiper axle by rocking slightly.

Remove the wiper arms nuts and the wiper arms from the wiper axles.

Remove the spray nozzles -arrow-.

Press the spray nozzles, with the water lines attached, through the plenum chamber opening.

Remove the rubber seal -4- and the plenum chamber cover -1-.

Scheme 141

Note. The threads of the shear bolts have been coated with a locking compound. A heat gun may be required to loosen the thread locking compound.

Saw off two rounded sides of the shear bolt heads so that two flat parallel surfaces result -arrows-.

Scheme 142

Using locking pliers, remove the shear bolts. Discard the shear bolts.

Insert a screwdriver -A- between the protective housing and the retaining plate -arrow-.

Scheme 143

Using a screwdriver -A-, pry the protective housing upward and sideways to remove from the retaining plate -arrow-.

Scheme 144

Disconnect the forward electrical harness connector -1-.

Lift up the locking mechanism -2- slightly.

Remove the Motronic Engine Control Module (ECM) -J220- from the retainer -arrow-.

Scheme 145

Disconnect the rear electrical harness connector.

Installation

Installation is performed in reverse order of removal. Note the following

The Motronic Engine Control Module (ECM) -J220- must be installed with the protective housing.

Use New shear bolts when installing the Motronic Engine Control Module (ECM) -J220-.

Motronic Engine Control Module (ECM) -J220- reprogramming

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

ADDITIONAL SIGNALS, CHECKING

The following table provides a link to all diagnostic modes that monitor all components and systems which influence the emission quality.

SPEED SIGNAL, CHECKING

The following procedure requires a test drive. Observe all Safety Precautions. Refer to SAFETY PRECAUTIONS .

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirements

1. The Speedometer -G21- OK.
2. The Motronic Engine Control Module (ECM) -J220- fuses OK.
3. Battery voltage at least 12.5 volts.
4. All electrical consumers such as, lights and rear window defroster, switched off.
5. A/C switched off.
6. Ground (GND) connections between engine/transmission/chassis OK.
7. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

Connect the scan tool.

Perform a road test with a vehicle speed greater than 5 Km/h.

Using the scan tool, Check the vehicle speed

Compare the vehicle speed on the scan tool to the Speedometer -G21-.

Specified value: a difference of no greater than 10%.

If the specified value was not obtained or no speed was displayed

Check the wiring from the Motronic Engine Control Module (ECM) -J220- to the Instrument Cluster Control Module -J285- for an open circuit, Short to Battery (+), or to Ground (GND).

Check the wiring connection for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

CAN-BUS TERMINAL RESISTANCE, CHECKING

Special tools and workshop equipment required

1. Multimeter.
2. Wiring diagram.

Test requirement

1. A CAN-Bus malfunction was recognized.
2. The Motronic Engine Control Module (ECM) - J220- fuses OK.
3. Battery voltage at least 12.5 volts.
4. All electrical consumers such as, lights and rear window defroster, switched off.
5. Vehicles with automatic transmission, shift selector lever into position "P" or "N".
6. A/C switched off.
7. Ground (GND) connections between engine/transmission/chassis OK.
8. Ignition switched off.

Test procedure

Perform a Preliminary Check to verify the customers complaint. Refer to PRELIMINARY CHECK

Start diagnosis

The Motronic Engine Control Module (ECM) -J220- communicates with other CAN-Bus capable control modules.

The control modules are connected by two data bus wires which are twisted together (CAN_High and CAN_Low), and exchange information (messages). Missing information on the CAN-bus is recognized as a malfunction by the Motronic Engine Control Module (ECM) -J220- and the other control modules connected to the CAN-Bus.

Trouble-free operation of the CAN-Bus requires that it have a terminal resistance. This central terminal resistance is located in the Motronic Engine Control Module (ECM) -J220-.

Procedure

Disconnect the Transmission Control Module (TCM) -J217- electrical harness connector.

Note. The Motronic Engine Control Module (ECM) -J220- must remain connected for the following step.

Using a Multimeter, check the Transmission Control Module (TCM) -J217- electrical harness connector terminals T68/3 to T68/25 for resistance.

Specified value: 60 to 72 ohms (at approx. 20° C)

If the specified value was not obtained

Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).

Check the wiring connection for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

If the specified value was obtained

Checking wiring

If the manufacturers test box is being used. Perform the following step.

Install the Adapter F/VAG1598 (68 Pin) VAG1598/22.

If the manufacturers test box is not being used. Perform the following step.

Remove the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Using a Multimeter, check the Transmission Control Module (TCM) -J217- electrical harness connector T68 to the Motronic Engine Control Module (ECM) -J220- electrical harness connector T80 for resistance.

Specified value: 1.5 ohms Max.

If the specified value was not obtained

Check the wiring connection for an open circuit, short circuit to Battery (+) or Ground (GND).

Check the wiring connection for damage, corrosion, loose or broken terminals.

If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring

Replace the Data Bus On Board Diagnostic Interface -J533-.

Erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY

Perform a road test to verify repair.

If the DTC does not return

Repair complete, Generate readiness code. Refer to READINESS CODE .

End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK

Replace the Motronic Engine Control Module (ECM) -J220-. Refer to MOTRONIC ENGINE CONTROL MODULE J220, REPLACING .

Assembly is performed in the reverse of the removal.

Final Procedures

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

1. Check the DTC memory. Refer to «DIAGNOSTIC MODE 03 - READ DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-03-read-dtc) .
2. If necessary, erase the DTC memory. Refer to «DIAGNOSTIC MODE 04 - ERASE DTC MEMORY»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__diagnostic-mode-04-erase-dtc) .
3. If the DTC memory was erased, generate readiness code. Refer to «READINESS CODE»(/volkswagen/new-beetle/a4-1997-2005/remont/cooling-fan/#20l-generic-scan-tool-engine-codes-aeg-hatchback__readiness-code) .

End of diagnosis.

See also:
• Fuel Injection System
• Battery, Disconnecting and Connecting
• PRELIMINARY CHECK
• DIAGNOSTIC MODE 04 - ERASE DTC MEMORY
• READINESS CODE
• DIAGNOSTIC MODE 03 - READ DTC MEMORY
• THROTTLE POSITION SENSOR G69 AND THROTTLE POSITION SENSOR G88, CHECKING
• Cooling System Component Overview, Engine Side
• CYLINDER BLOCK AND COMPONENTS OVERVIEW
• CRANKSHAFT ASSEMBLY OVERVIEW
• DIAGNOSTIC MODE 05 - READ OXYGEN SENSOR MONITORING TEST RESULTS
• EXHAUST MANIFOLD, FRONT EXHAUST PIPE AND ATTACHMENTS ASSEMBLY OVERVIEW [for engine(s) AEG]
• DIAGNOSTIC MODE 06 - READ TEST RESULTS FOR SPECIFIC DIAGNOSTIC FUNCTIONS
• SAFETY PRECAUTIONS
• CLEAN WORKING CONDITIONS
• TECHNICAL DATA
• OXYGEN SENSOR HEATER Z19, CHECKING
• OXYGEN SENSOR HEATER Z28, CHECKING
• MASS AIR FLOW SENSOR G70, CHECKING
• THROTTLE VALVE CONTROL MODULE J338, CHECKING
• ENGINE COOLANT TEMPERATURE SENSOR G62, CHECKING
• INTAKE AIR TEMPERATURE SENSOR G42, CHECKING
• ENGINE SPEED SENSOR G28, CHECKING
• FUEL INJECTORS N30, N31, N32, N33, CHECKING
• MOTRONIC ENGINE CONTROL MODULE J220, REPLACING
• HEATED OXYGEN SENSOR G39, CHECKING
• OXYGEN SENSOR HEATER AFTER CATALYTIC CONVERTER G108, CHECKING
• FUNCTION
• VOLTAGE SUPPLY, CHECKING
• SPEED SIGNAL, CHECKING
• CAN-BUS TERMINAL RESISTANCE, CHECKING