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Diagnostic Aids

Perform this test when instructed by QUICK TEST. This test is only intended to diagnose:

  1. 1) Continuous Memory DTC P1380: Check For KOEO & KOER DTCs

    This DTC indicates Comprehensive Component Monitor (CCM) failed due to VCT circuit voltage falling below a calibrated limit for a calibrated amount of time. Possible causes for this fault are:
    • VCT Circuit Open Or Shorted
    • VPWR Circuit Open
    • Faulty PCM
    • VCT Solenoid Open Or Shorted

    Start engine. Ensure engine is at normal operating temperature. Perform KOEO ON-DEMAND SELF-TEST  and KOER ON-DEMAND SELF-TEST  . If KOEO or KOER DTC P1380 is present, go to next step. If KOEO or KOER DTC P1380 is not present, fault may be intermittent. Disconnect PCM connector(s) and VCT connector. Inspect connectors for loose, damaged or corroded terminals. Repair as necessary and retest. If no faults are found, go to TEST Z, step  1).

  2. 2) Check VPWR Voltage At VCT Solenoid Valve Connector

    Disconnect VCT solenoid connector. Turn ignition switch to ON position. Using a DVOM, measure voltage of VPWR circuit between negative battery terminal and VCT solenoid harness connector. See Fig 1. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, repair open in VPWR circuit.
    Fig 1: Identifying Variable Cam Timing (VCT) Solenoid Wiring Harness Connector Terminals
    G00035650Courtesy of FORD MOTOR CO.

  3. 3) Check VCT Circuit For Open In Harness

    Turn ignition switch to OFF position. Disconnect PCM connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Using a DVOM, measure resistance of VCT circuit between PCM harness connector and VCT solenoid valve harness connector. See Fig 1. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in VCT circuit.

  4. 4) Check VCT Circuit For Short To Ground & VPWR In Harness

    Using a DVOM, measure resistance between PCM harness connector VCT terminal and PWR GND, SIG RTN and VPWR terminals. See WIRING DIAGRAMS article. See Figure and Fig 1 . If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between VCT circuit and PWR GND, SIG RTN or VPWR circuits.

  5. 5) Check VCT Solenoid Valve Resistance

    Using a DVOM, measure resistance between VCT solenoid valve connector terminals. If resistance is 3-6 ohms, go to next step. If resistance is not 3-6 ohms, replace VCT solenoid valve.

  6. 6) Check VCT Solenoid Valve For Short To Case

    Using a DVOM, measure resistance between each VCT solenoid valve connector terminal and VCT solenoid valve case. If both resistance measurements are more than 10 k/ohms, replace PCM. If either resistance measurement is 10 k/ohms or less, replace VCT solenoid valve.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 6) to step 11). No test procedures have been omitted.

  7. 11) DTC P1381 Or P1383: Check VCT For Proper Operation

    DTC P1381 is set when Comprehensive Component Monitor (CCM) detects camshaft timing exceeded a maximum calibrated value or remained in an advanced position. Possible causes are:
    • Camshaft Timing Improperly Set
    • No Oil Flow To VCT Piston Chamber
    • Low Oil Pressure
    • VCT Solenoid Valve Stuck Closed
    • Camshaft Advance Mechanism Binding (VCT Unit)

    DTC P1383 is set when Comprehensive Component Monitor (CCM) detects camshaft timing exceeded a maximum calibrated value or remained in a retarded position. Possible causes are:

    • Camshaft Timing Improperly Set
    • Continuous Oil Flow To VCT Piston Chamber
    • VCT Solenoid Valve Stuck Open
    • Camshaft Advance Mechanism Binding (VCT Unit)

    Start engine. Perform KOER ON-DEMAND SELF-TEST . If KOER DTC P1381 or P1383 is present, go to next step. If KOER DTC P1381 or P1383 is not present, fault may be intermittent. Go to TEST Z, step  1).

  8. 12) Check Camshaft Timing

    Check camshaft timing. See appropriate article in ENGINES. Repair as necessary. If camshaft timing is okay, camshaft advance mechanism is unable to move. Repair or replace VCT unit.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 12) to step 15). No test procedures have been omitted.

  9. 15) Continuous Memory DTC P1380 (Only)

    This DTC indicates Comprehensive Component Monitor (CCM) failed due to VCT circuit voltage falling below a calibrated limit for a calibrated amount of time. Possible causes for this fault are:
    • VCT Circuit Open Or Shorted
    • VPWR Circuit Open
    • Faulty PCM
    • VCT Solenoid Open Or Shorted

    Connect scan tool to Data Link Connector (DLC). Start engine and allow to idle. Ensure engine is at normal operating temperature. Using scan tool, select RCAM PID from PID/DATA MONITOR & RECORD menu. Increase engine speed to 1500 RPM and hold. While observing RCAM PID value, wiggle small sections of wiring harness starting at VCT solenoid working toward PCM. If RCAM PID value changes from positive to negative, a momentary open or short circuit is indicated. If engine starts to run rough, VCT circuit may be intermittently shorted to GND causing camshaft to fully retard. If a fault is indicated, isolate fault and repair as necessary. If no fault is indicated, fault may be intermittent. Service any other DTCs that are present. If no other DTCs are present, go to TEST Z, step  1).

    10. NOTE: Testing is performed with cooling fan off.

  10. 16) Continuous Memory DTC P1381 (Only)
    DTC P1381 is set when Comprehensive Component Monitor (CCM) detects camshaft timing exceeded a maximum calibrated value or remained in an advanced position. Possible causes are:
    • Camshaft Timing Improperly Set
    • No Oil Flow To VCT Piston Chamber
    • Low Oil Pressure
    • VCT Solenoid Valve Stuck Closed
    • Camshaft Advance Mechanism Binding (VCT Unit)

    Connect scan tool to Data Link Connector (DLC). Start engine and allow to idle. Ensure engine is at normal operating temperature. Using scan tool, select CAMERR PID from PID/DATA MONITOR & RECORD menu. Observe CAMERR PID value while increasing and decreasing engine speed from 1500 RPM to idle several times. If CAMERR PID value does not change from negative to positive, intermittent DTC P1381 may be caused by faulty VCT unit. Repair or replace VCT unit as necessary. If CAMERR PID value changes from negative to positive, fault may be intermittent. Go to TEST Z, step  1).

    11. NOTE: Testing is performed with cooling fan off.

  11. 17) Continuous Memory DTC P1383 (Only)
    DTC P1383 is set when Comprehensive Component Monitor (CCM) detects camshaft timing exceeded a maximum calibrated value or remained in a retarded position. Possible causes are:
    • Camshaft Timing Improperly Set
    • Continuous Oil Flow To VCT Piston Chamber
    • VCT Solenoid Valve Stuck Open
    • Camshaft Advance Mechanism Binding (VCT Unit)

    Connect scan tool to Data Link Connector (DLC). Start engine and allow to idle. Ensure engine is at normal operating temperature. Using scan tool, select CAMERR PID from PID/DATA MONITOR & RECORD menu. Observe CAMERR PID value while increasing and decreasing engine speed from 1500 RPM to idle several times. If engine runs rough and CAMERR PID value indicates 50 percent or more error, intermittent DTC P1383 may be caused by faulty VCT unit. Repair or replace VCT unit. If engine does not run rough and PID value indicates less than 50 percent error, fault may be intermittent. Go to TEST Z, step  1).

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