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HOMESERVICE MANUALSFORD2004ECONOLINE E150, VAN CARGO, 4.6 WREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSISENGINE CONTROLS - POWERTRAIN DTC CHARTS & DESCRIPTIONS - CNG, FLEX-FUEL & GASOLINEDIAGNOSTIC TROUBLE CODE (DTC) CHARTSP0645
2004 Ford Econoline E150, Van Cargo, 4.6 W

Diagnostic Trouble Code (DTC) Charts: P0645

2004 Ford Econoline E150, Van Cargo, 4.6 WSECTION P0645
P0645

Description:  Monitors the wide open throttle A/C cutoff (WAC) circuit output from the PCM. The test fails if: When the PCM grounds the WAC circuit, excessive current draw is detected on the WAC circuit; or, with the WAC circuit not grounded by the PCM, voltage is not detected on the WAC circuit (the PCM expects to detect VPWR voltage coming through the WAC relay coil to the WAC circuit).
Possible Causes: 
  • Open or shorted WAC circuit.
  • Damaged WAC relay (or CCRM).
  • Open VPWR circuit to the WAC relay.
  • Damaged PCM.
Diagnostic Aids: 
  • The A/CCR control circuit can be monitored using the WACF & WAC PID.
  • When the WACF PID reads YES, a fault is currently present.
  • An open circuit or short to ground can only be detected when the PCM is not grounding the circuit.
  • A short to power can only be detected when the PCM is grounding the circuit.
  • During the KOEO and KOER self-test, the WAC circuit is cycled on and off.
  • Verify the A/C and defrost were off during the KOEO and KOER self-tests. Check the ACCS PID to verify.
  • If the vehicle is not equipped with A/C, DTC P1460 can be ignored.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Mustang GO to X: Constant Control Relay Module (CCRM) STEP 49 GO to X: Constant Control Relay Module (CCRM) STEP 49 GO to X: Constant Control Relay Module (CCRM) STEP 59
All Others GO to KM: Air conditioning clutch relay circuit STEP 1 GO to KM: Air conditioning clutch relay circuit STEP 1 GO to KM: Air conditioning clutch relay circuit STEP 14
RENDER: 1.0x

NO RELATED

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