P1539
DTC P1539CIRCUIT DESCRIPTION
The powertrain control module (PCM) will activate the A/C clutch relay when the PCM detects that A/C has been requested. When the PCM activates the relay, voltage should be present at both the A/C compressor clutch and the A/C compressor clutch supply voltage circuit at the PCM. If voltage is detected when A/C is not requested this DTC sets.
CONDITIONS FOR RUNNING THE DTC
The ignition is turned ON.
CONDITIONS FOR SETTING THE DTC
- The PCM detects a voltage on the A/C compressor clutch supply voltage circuit when the A/C is not requested.
- The condition is present for at least 20 seconds.
ACTION TAKEN WHEN THE DTC SETS
- The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
- The PCM stores the failure records.
- The A/C compressor clutch is disabled.
CONDITIONS FOR CLEARING THE DTC
- The DTC will become history if the PCM no longer detects a failure.
- The history DTC will clear after 40 fault-free ignition cycles.
- The DTC can be cleared with a scan tool.
TEST DESCRIPTION
Steps 1-3:
Steps 4-8:
The numbers below refer to the step numbers on the diagnostic table.
3. Verifies the condition is present.
4. Determines if the A/C compressor clutch relay is at fault.
5. Determines if the PCM is at fault or the A/C compressor clutch supply voltage circuit is at fault.
7. Perform the recalibration procedure for the PCM.