Trouble Code Conditions

Special Tools:
- 981 3190
- 998 8686

Trouble Code Conditions
- System pressure solenoid STH controls the system pressure in the transmission. The solenoid is controlled by an amplifier in the transmission control module (TCM) output. The transmission control module uses the amplifier to control the current to the solenoid. A low amperage provides a high system pressure and a high amperage (approx. 1A) provides a low system pressure. This amperage is primarily affected by throttle position. Diagnostic Trouble Code (DTC) AT-132 is stored if the TCM registers that the amperage in the TCM circuit is too high. Solenoid STH cannot control system pressure.

Substitute value(s)
- The transmission control module limp-home program has been initiated.

Possible source(s)
- Defective transmission control module.

Fault symptom(s)
- The combined instrument panel warning lamp flashes.
- Deterioration in performance because the TCM prevents activation of the solenoids, this stops gear-shifting. The transmission only operates in 3rd gear in positions 3 and L, 4th gear in position D and reverse in position R. Shifting can only be carried out manually between 3rd, 4th and reverse gears.
- No system pressure solenoid STH control resulting in constant maximum system pressure leading to harsher shifting and gear meshing.
- No lock-up function.

CAUTION: The ECM posts a DTC when the transmission sends a malfunction indicator lamp (MIL) request. Erase the DTC in the ECM when the transmission fault has been repaired.

- Start fault-tracing. Short Circuit In STH Amplifier