DTC P0645: - Air Conditioning Clutch Relay (A/CCR) Control Circuit

2009 Ford Edge Sport, FWDSECTION DTC P0645: - Air Conditioning Clutch Relay (A/CCR) Control Circuit
DTC P0645: - AIR CONDITIONING CLUTCH RELAY (A/CCR) CONTROL CIRCUIT

Description:  Monitors the A/CCR circuit output from the powertrain control module (PCM). The test fails when the PCM grounds the A/CCR circuit, excessive current draw is detected on the A/CCR circuit; or, with the A/CCR circuit not grounded by the PCM, voltage is not detected on the A/CCR circuit (the PCM expects to detect VPWR voltage coming through the A/CCR relay coil to the A/CCR circuit).
Possible Causes: 
  • Open or short A/CCR circuit
  • Damaged A/CCR relay
  • Open VPWR circuit to the A/CCR relay
Diagnostic Aids:  The A/CCR control circuit can be monitored using the WACF and WAC PID.
When the WACF PID reads YES, a concern is present.
An open circuit or short to ground can only be detected when the PCM is not grounding the circuit.
A short to voltage can only be detected when the PCM is grounding the circuit.
During the key on engine off (KOEO) and key on engine running (KOER) self-test, the WAC circuit is cycled on and off. Verify the A/C and the defrost were OFF during the KOEO and KOER self-tests. Check ACCS PID to verify. If the vehicle is not equipped with A/C, ignore DTC P0645.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test KM .
RENDER: 1.0x

NO RELATED

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