DTC 132

EAK.Code 1-3-2

1-3-2 Fault in Transmission Control Module (TCM)

DTC information


Conditions for DTC






Solenoid STH controls the transmission system pressure. The solenoid is controlled by an integral amplifier (driver stage) on the output of the transmission control module (TCM). The TCM uses the driver stage to regulate the current supplied to the solenoid. A low amperage gives a high system pressure and a high amperage (approx. 1A) gives a low system pressure. The amperage of this current is affected primarily by the throttle position. If the TCM registers that the amperage on the circuit within the TCM is too high, DTC 1-3-2 is set. Solenoid STH cannot then control the system pressure.

Substitution value

The TCM "Limp-home" program has been initiated and the transmission operates only in 4th gear.

Defect cause






- Incorrect supply voltage to the system
- Contact resistance in connections.
- Fault in TCM

Fault symptom

- Poor performance due to the transmission operating only in 4th gear.

- Fault-tracing starts with EAK1.



EAK1

Checking voltage drop over signal ground and power ground






- Ignition OFF
- Connect test box and check ground points as per GB1-GB2 GB. Connecting the Test Box
- Ignition ON.
- Turn on as many power consuming items as possible.

Use a voltmeter to measure between #20 (#A20) and #29 (#A29) on the test box.
The voltmeter should read less than 0.6V.






If reading is OK:
-^ Checking voltage drop over signal ground EAK2.

If reading is incorrect:
- Check ground points 31/32 and 31/33, the cables between the ground points and the TCM #A20 and #A29, and the TCM connector for a break as per FA2 and contact resistance and oxidation as per FA6. FA. Checking Wiring and Connections

Then continue with: Checking voltage drop over signal ground EAK2.



EAK2

Checking voltage drop over signal ground

- Ignition OFF
- Test box connected
- Connect a test box to the engine control module ECM (MFI Fenix 5.2, LH 3.2, or Motronic 4.3).
- Control modules connected
- Ignition ON.
- Turn on as many power consuming items as possible.






Connect a voltmeter between the transmission test box #20 (#A20) and the ECM module test box:

- Fenix 5.2 MFI control module: #42 (#A42) (signal ground, control module)
- LH 3,2 MFI control module: #20 (#A20) (signal ground, control module)
- Motronic 4.3 MFI control module: #42 (#A42) (signal ground, control module)

The voltmeter should read less than 0.10 V.






If reading is OK:
- Checking supply voltage (15 supply) EAK3.

If reading is incorrect:
- Check ground point 31/33, wiring between the ground point and the TCM and ECM modules for contact resistance and oxidation as per FA6. FA. Checking Wiring and Connections

Then continue with: Checking supply voltage (15 supply) EAK3.



EAK3

Checking supply voltage (15 supply





- Ignition ON.

Use a voltmeter to measure between #30 (#A30) and #29 (A#29) on the test box.
The voltmeter should register approx. battery voltage.

If reading is OK:
- Checking supply voltage (30 supply) EAK4.

If reading is incorrect:
- Check the cable between fuse 11/1 and the TCM #A30 for breaks as per FA2. FA. Checking Wiring and Connections

Then continue with: Checking supply voltage (30 supply) EAK4.



EAK4

Checking supply voltage (30 supply)






- Ignition ON.

Use a voltmeter to measure between #10 (#A1O) and #20 (#A20) on the test box.
The voltmeter should register approx. battery voltage.

If reading is OK:
- Checking the transmission control module (TCM) EAK5.

If reading is incorrect:
- Check the cable between the positive terminal on the battery and TCM #A10 for breaks as per FA2. FA. Checking Wiring and Connections

Then continue with: Checking the transmission control module (TCM) EAK5.


EAK5

Checking the transmission control module (TCM)






- Ignition OFF
- Disconnect test box Connect TCM
- Ignition ON.
- Clear DTCs
- Test drive the car at a speed higher than 25 km/h (15 mph).






If the DTC is set again:
- Try a new TCM as per AB1-AB2.