Throttle Position Sensor/Accelerator Pedal Position Sensor 2, Checking

Special Tools And Workshop Equipment 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 connections between engine/transmission/chassis OK.

Test Procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start Diagnosis 

-- Remove the drivers side storage compartment. Refer to Removal and Installation .

-- 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.

-- Using a multimeter, check the following wiring connections for voltage.

Throttle Position (TP) Sensor -G79- /Accelerator Pedal Position Sensor 2 -G185- electrical harness connector terminals	Specified value
1 to Ground	near 5 V
1 to 5	near 5 V
2 to Ground	near 5 V
2 to 3	near 5 V

-- Switch the ignition OFF.

If the specified value was Not obtained: 

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) -J623-. Refer to the appropriate Service Information.

-- Using a multimeter, check the Throttle Position (TP) Sensor -G79- /Accelerator Pedal Position Sensor 2 -G185- electrical harness connector terminals to the Motronic Engine Control Module (ECM) -J623- electrical connector T94 for an open circuit.

Throttle Position (TP) Sensor -G79- /Accelerator Pedal Position Sensor 2 -G185- electrical harness connector terminals	Motronic Engine Control Module (ECM) -J623- electrical connector T94 terminals or test box sockets
1	81
2	82
3	35
4	83
5	11
6	61

Specified value: 1.5 Ω max. 

If the specified value was Not obtained: 

-- Check the wiring for a short circuit to each other, Battery (+), and Ground or high resistance).

-- 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 the Throttle Position (TP) Sensor -G79- /Accelerator Pedal Position Sensor 2 -G185-. Refer to the appropriate Service Information.

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

-- Replace the Motronic Engine Control Module (ECM) -J623-. Refer to the appropriate Service Information.

-- Install the drivers side storage compartment. Refer to the appropriate Service Information.

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 .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .