DTC P1D9A
DTC P1D9A: PCU Electric Coolant Pump Circuit
General Description
The power control unit (PCU) controls the PCU electric coolant pump according to the rotational speed of the PCU electric coolant pump calculated from the frequency (duty fixed to 50 %) detected from the NEWP terminal. If, when a trouble with EWP input duty signal, leak of coolant, or another event leads to unexpected small load and then over rotation, the NEWP output of "intermittent operation" output by the EWP 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 | 1.5 seconds or more |
| DTC Type | Two drive cycles, MIL on, POWER SYSTEM indicator on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| PCU electric coolant pump output duty change instructions | 2 seconds | - |
| 12 volt battery voltage | 10 V | - |
| PCU electric coolant pump output duty | 35 % | - |
Malfunction Threshold
The NEWP output value is more than 164.8 Hz for at least 1.5 seconds.
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
- Water pipe clogged
- PCU electric coolant pump failure
- PCU internal failure
Confirmation Procedure
Operating Condition
Turn the vehicle to the ON mode.
With the HDS
Select the ELECTRIC WATER PUMP TEST in the Electric Powertrain FUNCTION TEST with the HDS. Then do the START.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the motor control module memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.
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.