DTC P0634
DTC P0634: PCU Internal Temperature Too High
General Description
The power control unit (PCU) monitors the board temperature sensor value to prevent malfunction of internal parts due to heat generation. If the board temperature sensor output temperature is out of a specified value for a specified time, the motor control module in the PCU detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 500 milliseconds or more |
| DTC Type | One drive cycle, MIL on, POWER SYSTEM indicator on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| High voltage side power supply voltage (6 V) | 5 V | - |
Malfunction Threshold
The output temperature from the board temperature sensor is more than 238 deg.F (114 deg.C) for at least 500 milliseconds.
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Water pipe leak
- PCU electric coolant pump failure
- PCU internal failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the motor control module memory.
Conditions for clearing the DTC
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.