Pinpoint Test 2: DTC P0A27 - Hybrid Battery Power Off Circuit
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PINPOINT TEST 2: DTC P0A27 - HYBRID BATTERY POWER OFF CIRCUIT
Normal Operation
With the engine running, the battery power off function may be triggered by an open condition in the front and/or rear inertia fuel shut off (IFS) switches, the high-voltage interlock circuit or the electrical interlock (EL I) circuit (fuse protected by the battery junction box [BJB] fuse 26 [5A]). The IFS switch opens and causes the battery power off mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the instrument cluster (IC) illuminates.
- DTC P0A27 (Hybrid Battery Power Off Circuit) - the BCM sets this DTC if any of the following conditions are met:
- BCM detects a thermistor temperature greater than 57°C (134°F) for at least one second.
- Contactor control is reported as closed while contactor status confirmed is reported as open for 10 seconds.
- High-voltage traction battery (HVTB) is overheated.
- It is possible for the PCM to set DTC P0A28 (Hybrid Battery Power Off Circuit Low) as a continuous fault.
Possible Causes
- Fuse
- Wiring, terminals or connectors
- HVTB
Diagnostic Procedure
