P1546

CIRCUIT 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 circuits at the PCM. If voltage is not detected when A/C is requested this C type DTC sets.

CONDITIONS FOR RUNNING THE DTC
The ignition is turned ON.
The A/C clutch is requested

CONDITIONS FOR SETTING THE DTC
The PCM commands the A/C ON and the PCM does not detect a voltage on the A/C clutch status line for more than 5 seconds.

ACTION TAKEN WHEN THE DTC SETS
- The PCM will not illuminate the malfunction indicator lamp (MIL).
- The PCM records the operating conditions at the time the diagnostic fails.
- The PCM stores this information in the Failure Records.
- The multifunction display (MFD) in the instrument cluster will display a message at key-on and key-off.

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

Step 1 - 4:

Step 5 - 12:

The numbers below refer to the step numbers on the diagnostic table.
3. Verifies that battery voltage is supplied to the A/C compressor clutch relay.
4. Tests if the A/C relay is at fault or the A/C compressor clutch supply voltage circuit is at fault. If the A/C compressor clutch engages, this indicates that the A/C compressor clutch supply voltage circuit is OK.
5. If the A/C clutch feedback signal parameter displays OFF, this indicates that the A/C compressor clutch supply voltage circuit is open between the splice and the PCM. If the A/C clutch feedback signal parameter displays ON, this indicates a faulty connection at the A/C compressor relay or a malfunctioning relay