Control Module: Testing and Inspection

Transmission Control Module Voltage Supply, Checking

• The Transmission Control Module (TCM) (J217) is a component of the Mechatronic unit in the transmission and cannot be serviced individually.

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Requirements

• The Transmission Control Module (TCM) (J217) fuses OK.

• The battery voltage must be at least 12.5 volts.

• The Ground (GND) connections at the transmission OK.

• The parking brake engaged.

• The selector lever of automatic transmission in position "P".

• All electrical consumers switched off.

• The ignition switched off.

Test sequence

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





- Check the electrical harness connector for damage, contact corrosion, or ingress of water.

If the electrical harness connector is not OK:

- Repair the malfunction.

If the electrical harness connector is OK:

Checking voltage

- Switch the ignition on.

- Using a Multimeter, check the Power Supply Relay (terminal 15) (J329) socket 2/87 to Ground (GND).

Specified value: battery voltage.

- Switch the ignition off.

If the specified value was not obtained:

- Check the wiring from the Power Supply Relay (terminal 15) (J329) socket 2/87 to the Transmission Control Module (TCM) (J217) electrical harness connector terminal 9 for an open circuit or a short circuit.

- If necessary, repair the faulty wiring connection.

If the specified value was obtained:

- Using a Multimeter, check the Transmission Control Module (TCM) (J217) electrical harness connector terminal 14 to Ground (GND).

Specified value: battery voltage.

If the specified value was obtained:

- Check the wiring from the Battery to the Transmission Control Module (TCM) (J217) electrical harness connector terminal 14 for an open circuit or a short circuit.

- If necessary, repair the faulty wiring connection.

If the specified value was obtained:

Checking Ground (GND)

- Using a Multimeter, check the Transmission Control Module (TCM) (J217) electrical harness connector terminals 13 and 16 to Ground (GND) for resistance.

Specified value: 1.5 ohms

If the specification was not obtained:

- Check the wiring for a an open circuit.

- If necessary, repair the faulty wiring connection.

If no malfunction is found in the wiring:

- Replace the Mechatronic unit in the transmission:.

Final procedures

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the Transmission Control Module (TCM) (J217) memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.