DTC 132

DK. DTC 1-3-2
1-3-2 TCM fault

Principle of operation

Solenoid STH controls the transmission fluid pressure. The solenoid is operated by a variable current from the TCM, the value of which is influenced primarily by the throttle. The pressure is low at high current levels (approx. 1 A). The line pressure is a maximum at low currents or when the current is interrupted.

Fault description

The TCM has interrupted the supply to solenoid STH on detecting excessive solenoid current due to a faulty TCM output. The emergency limp-home program is activated and the transmission operates only in 4th gear (i.e. no gearshifting can be performed). The MIL on the panel lights.
Troubleshooting should indicate if the TCM is actually faulty.





Circuit description

The circuit consists of the TCM, connectors and solenoid STH in the transmission.





1
Checking TCM supply

- Switch off ignition.
- Connect break-out box between TCM and wiring.
- Switch on ignition.

Supply between ignition switch and power ground

Connect voltmeter across # 14 (+12 V) and # 11 (PG) on break-out box.

- Instrument should indicate battery voltage.

Supply between battery and signal ground

Connect voltmeter across # 30 (+12 V) and # 12 (SG) on break-out box.

- Instrument should indicate battery voltage.

If either reading is incorrect, each lead should be checked as described in Testing and Inspection. Component Tests and General Diagnostics

Proceed to following step.

2
Checking ground terminals

- Switch on ignition.

Connect voltmeter across # 11 (PG) and # 12 (SG).

- Instrument should indicate less than 0.7 volt, otherwise ground connections are poor. In this case, check leads and connections to ground terminals as described in Testing and Inspection. Component Tests and General Diagnostics

If readings are correct, return to Testing and Inspection. Diagnostic Procedures

If DTC recurs following test drive, try with new TCM.