DTC P0634
DTC P0634: Control Module Internal Temperature "A" Too High
General Description
The transmission control module (TCM) shuts down if the internal temperature increases to a specified value to prevent damaging the hardware. If the temperature in the TCM is a specified value for a specified duration, the TCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 1 second or more |
| DTC Type | One drive cycle, MIL on, A/T gear position indicator blinks |
Enable Conditions
| Condition | ||
|---|---|---|
| Vehicle | ON mode | |
Malfunction Threshold
The internal temperature of the TCM exceeds 270 °F (132 °C) for at least 1 second.
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- TCM internal failure
Confirmation Procedure
Operating Condition
- 1.
Start the engine.
- 2.
Drive the vehicle for a while.
- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
With the HDS
None.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the A/T gear position indicator blinks, the MIL comes on, and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory.
Conditions for clearing the DTC
The A/T gear position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.