Trouble Code Conditions

SPECIAL TOOLS
Test box tool No. 981 3190, or equivalent
Volvo scan tool No. 998 8686, or equivalent

CONDITION
The gear-shift position sensor signals provide the Transmission Control Module (TCM) with data on the gear selector position. This information is transmitted by grounding a combination of signals A, B. C and PA inside the gear-shift position sensor. Diagnostic Trouble Code (DTC) AT-313 is posted if the TCM registers an unacceptable combination of A, B. C and PA for a period of 5 seconds as shown below.





SUBSTITUTE VALUE
The TCM limp-home program has been initiated.

POSSIBLE SOURCE
- Short-circuit to supply voltage or ground in the signal cable
- Open-circuit in signal cable
- Gear-shift position sensor incorrectly adjusted
- Defective gear-shift position sensor
- Contact resistance in terminals.

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 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 system pressure solenoid STH control resulting in constant maximum system pressure leading to harsher shifting and gear meshing.
- No lock-up function.

CAUTION: The gear-shift position sensor cannot be short-circuited to supply voltage.

NOTE:
- The Motronic 4.4 Engine Control Module (ECM) posts a DTC when the transmission sends a Malfunction Indicator Lamp (MIL) request.
- Erase this DTC in the Motronic ECM when the transmission fault has been repaired.

TESTING PROCEDURE
- Start fault-tracing at, Faulty signal. Faulty Signal