Throttle Position Sensor/Accelerator Pedal Position Sensor 2, Checking

Throttle Position Sensor/Accelerator Pedal Position Sensor 2, Checking

Special tools, testers and auxiliary items required
- Multimeter.
- Wiring diagram

Test requirement
- The Motronic Engine Control Module (ECM) J623 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.

NOTE: Use only gold-plated terminals when servicing the electrical harness connector terminals in Throttle Position (TP) Sensor G79 / Accelerator Pedal Position Sensor 2 G185.

Test sequence
- Remove the drivers side storage compartment.







- Disconnect the Throttle Position (TP) Sensor G79 / Accelerator Pedal Position Sensor 2 G185 6-pin electrical harness connector - 2 -.

Checking voltage supply and wiring
- Switch the ignition on.







- Switch the ignition on.
- Using a Multimeter , check the following wiring connections for voltage.

Throttle Position (TP) Sensor Specified value
G79/Accelerator Pedal Position
Sensor 2 G185 electrical
harness connector terminal
1 to Ground (GND) about 5 V
1 to 5 about 5 V
2 to Ground (GND) about 5 V
2 to 3 about 5 V

- Switch the ignition off.

If the specification is not obtained:

If the manufacturers test box is being used. Perform the following step.
- Install the test box.
- Using a Multimeter , check the Throttle Position (TP) Sensor G79 / Accelerator Pedal Position Sensor 2 G185 6-pin electrical harness connector terminals to the Motronic Engine Control Module (ECM) J623 electrical connector T121 for an open circuit according to wiring diagram.

Throttle Position (TP) Sensor Motronic Engine Control Module
G79/Accelerator Pedal Position (ECM) J623 electrical connector
Sensor 2 G185 electrical T121 terminals or test box socket
harness connector terminals
1 72
2 73
3 36
4 35
5 33
6 34

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).
- 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 the voltage supply was OK:
- Replace the Throttle Position (TP) Sensor G79 / Accelerator Pedal Position Sensor 2 G185.

If no malfunction is detected in the wiring and if the voltage supply was not OK:
- Replace the Motronic Engine Control Module (ECM) J623.
- Install the drivers side storage compartment.

Final procedures
After repair work, the following work steps must be performed in the following sequence:
1. Check the DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. If necessary, erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. If the DTC memory was erased, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes