DTC P1448: Intelligent Power Unit (IPU) Module Fan Problem (63) (2014-15)
General Description
To manage the temperature of the DC-DC converter, the motor power inverter (MPI) module, and the battery pack, the electric powertrain system is equipped with a high voltage battery module fan. When a malfunction occurs in the high voltage battery module fan, charging and power supplying to the 12 volt battery is disabled due to temperature increase. A malfunction in the high voltage battery module fan is detected to avoid problems caused by overheating. If the IPU module fan is functioning normally, when the battery condition monitor module operates the high voltage battery module fan, it should be operated within a specified speed range. The battery condition monitor module compares the actual high voltage battery module fan speed to the high voltage battery module fan duty cycle, and if the difference exceeds a specified value, the battery condition monitor module detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type, OBD Status
| Execution | Continuous |
| Sequence | None |
| Duration | 16 seconds or more |
| DTC Type | Two drive cycles, MIL on, POWER SYSTEM indicator on |
| OBD Status | PASSED/FAILED/NOT COMPLETED (STILL TESTING) |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Target high voltage battery module fan speed | 1, 000 rpm | - |
| Battery condition monitor module power-supply voltage | 11.4 V | - |
| Vehicle | ON mode | |
Malfunction Threshold
The difference between the target high voltage battery module fan speed and actual speed is equal to or more than the value in the table below continuously for 16 seconds.
| Target high voltage battery module fan speed (rpm) | 500 | 1, 000 | 1, 500 | 2, 000 | 2, 500 | 3, 000 | 3, 500 | 4, 000 | 4, 500 |
| Difference with the high voltage battery module fan speed (rpm) | 253 | 507 | 963 | 1, 284 | 1, 641 | 1, 992 | 2, 324 | 2, 686 | 3, 054 |
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.
- High voltage battery module fan failure
- High voltage battery module fan line failure
- Battery condition monitor module failure
Confirmation Procedure
Operating Condition
Turn the vehicle to the ON mode.
With the HDS
Do the BATTERY FAN TEST in the INSPECTION MENU with the HDS.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the battery condition monitor 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 or the battery condition monitor module reset.