Trouble Code Conditions

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Trouble Code Conditions
- The oil temperature sensor sends a signal to the transmission control module (TCM) which is used for functions such as temperature controlled lock-up and initiating high-temperature programs. The sensor has an NTC (negative temperature coefficient) resistor. The signal decreases with increasing oil temperature. Diagnostic trouble code (DTC) AT-235 is stored it the transmission control module receives a signal from the oil temperature sensor corresponding to a temperature above approx. +140°C (284°F) for approx. 5 seconds.

Substitute value(s)
- None.

Possible source(s)
- Short-circuit to ground in signal cable.
- Defective oil temperature sensor.
- Mechanical fault in the transmission.
- The transmission has been exposed to extreme load and temperature.

Fault symptom(s)
- The warning light flashes when the diagnostic trouble code is stored and stops flashing when the transmission control module receives a signal that oil temperature has fallen below approx. +135°C (275°F).

NOTE: If you suspect that the transmission oil temperature has exceeded +140°C (284°F) it must be changed.

- Start fault-tracing. Signal Too High