With Generic Scan Tool
Throttle Valve Control Module J338, checking
Note: Use only gold-plated terminals when servicing terminals in harness connector of Mass Air Flow (MAF) Sensor J338.
Special tools, testers and auxiliary items required
- Multimeter
- Wiring diagram
Test requirements
- The Engine Control Module (ECM) J220 fuses OK.
- Battery voltage at least 12.5 volts.
- All electrical consumers such as, lights and rear window defroster, switched off.
- Vehicles with automatic transmission, shift selector lever into position "P" or "N".
- A/C switched off.
- Ground (GND) connections between engine/transmission/chassis OK.
- Throttle valve must not be damaged or dirty.
- Coolant Temperature at least 80�C.
Function
Throttle valve operation occurs by an electric motor ( Throttle Position (TP) Actuator V60 ) in Throttle Valve Control Module J338 . It is operated by Engine Control Module (ECM) J220 according to specifications of Throttle Position (TP) Sensor G69 / Throttle Position (TP) Sensor G88.
Components of Throttle Valve Control Module J338:
- Throttle Position (TP) Actuator V60
- Throttle Position (TP) Sensor G69
- Throttle Position (TP) Sensor G88
Test procedure
- Perform a preliminary check to verify the customers complaint.
Start diagnosis
- 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 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-.
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.
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 Engine Control Module (ECM) J220.
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 7 for voltage.
Specified value: at least 4.5 V
- Switch the ignition off.
If the specification was not obtained:
If the manufacturers test box is being used. Perform the following step.
- Install the Test Box 80 Pin VAG1598/22. Connecting VAG 1598/22 Test Box
If the manufacturers test box is not being used. Perform the following step.
- Remove the Engine Control Module (ECM) J220.
- Using a Multimeter, check the Throttle Drive (for Electronic Power Control (EPC)) G186 at Throttle Valve Control Module J338 electrical harness connector terminals to the Engine Control Module (ECM) J220 electrical harness connector T80 terminals for an open circuit.
Specified value: 1.5 Ohms max.
If the specification is not obtained:
- Check the wiring for a short circuit to each other, Battery (+), and 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:
- Erase the DTC memory. Diagnostic Mode 04: Reset/Delete Diagnostic Data
- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Audi Drive Cycle/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 Engine Control Module (ECM) J220.
- Assembly is performed in the reverse order of removal.
Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.
End of diagnosis.