Advanced Diagnostics

DTC P15A4 (81): A/C Compressor Driver Relay Stays Activated




General Description
The A/C compressor driver controls switching of the A/C compressor contactor and detects arcing. When the A/C compressor contactor arcs, it may stick on, and, the A/C compressor driver sends the sticking information to the battery condition monitor (BCM) module by the IMA-CAN communication. When the BCM module receives the sticking information, a malfunction is detected and a DTC is stored.




Monitor Execution, Sequence, Duration, DTC Type, OBD Status




Enable Conditions

Malfunction Threshold
The BCM module receives A/C contactor sticking information.

Driving Pattern
1. Start the engine.
2. Let the engine idle for at least 5 minutes at an outside air temperature of 41 °F(5 °C) or more. (If the outside air temperature is 77 °F (25 °C) or more, idling is not necessary.)
3. Turn the auto A/C switch ON.
4. Set the A/C temperature to 77 °F (25 °C).

Diagnosis Details

Conditions for illuminating the IMA system indicator
When a malfunction is detected, the I MA system indicator comes on and the DTC and the freeze frame data are stored in the BCM memory.

Conditions for clearing the IMA system indicator
The IMA system indicator will be cleared if the malfunction does not recur during the next trip in which the diagnostic runs.

The IMA system indicator, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.