Diagnostic Trouble Code (DTC) Information

DTC information
981 3190 Replaced by 9511428 981 3190 Replaced by 951 1428 998 8686 Replaced by 9511532 998 8686 Replaced By 9511532
Condition





System pressure solenoid STH controls system pressure in the transmission. The solenoid is controlled by an amplifier in the transmission control module (TCM) output. The transmission control module (TCM) 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-123 is posted if the transmission control module (TCM) registers a short-circuit to supply voltage in the solenoid STH circuit causing a high amperage. Solenoid STH cannot control system pressure.

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

Possible source
- Short-circuit to supply voltage in the signal cable.
- Defective solenoid STH.

Fault symptom[s]
- The combined instrument panel warning lamp flashes.
- Deterioration in performance because the transmission control module (TCM) prevents activation of the solenoids, this stops gear-shifting. The transmission operates only 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 gear.
- No lock-up function.

Caution! There is a danger that system pressure may be too low, which will result in wear.

Note! The Motronic 4.4 engine control module (ECM) posts a diagnostic trouble code (DTC) when the transmission sends a malfunction indicator lamp (MIL) request. Erase this diagnostic trouble code (DTC) in the Motronic engine control module (ECM) when the transmission fault has been repaired.