Trouble Code Conditions

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- 981 3190
- 998 8686





Trouble Code Conditions
- 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 signals A, B, C and PA in various combinations. The grounding occurs inside the gear position sensor. Diagnostic trouble code (DTC) AT-313 is stored if the transmission control module registers an unacceptable combination of A, B, C and PA for a period of 5 seconds as shown below.





- = 0-2 V below battery voltage (U bat)
o = ground (U low)

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

Possible source(s)
- 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 transmission control module 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 gear-shift position sensor will malfunction if there is a short-circuit to supply voltage.

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

- Start fault-tracing. Faulty Signal