AutoZone 1968 Buick Riviera 7.0L 4BL OHV 8cyl | Repair Guides | Diagnostics | Diagnostic Trouble Codes | 3.0l V6 - Auto 7 | AutoZone.com

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    Ford Freestyle 2005

    3.0L V6 - Auto 7

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    Trouble Code: P1461



    A/C Pressure Sensor Circuit High Input

    Possible Causes:



    ACP sensor circuit shorted to VREF or to power (VPWR)
     
    ACP sensor circuit is open, or the ground circuit is open
     
    ACP sensor is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1462



    A/C Pressure Sensor Circuit Low Input

    Possible Causes:



    ACP sensor circuit shorted to VREF or to power (VPWR)
     
    ACP sensor circuit is open, or the ground circuit is open
     
    ACP sensor is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1463



    A/C Pressure Sensor Insufficient Pressure Change

    Possible Causes:



    A/C system mechanical failure, or A/C clutch always engaged
     
    ACP sensor signal open, or sensor ground circuit open
     
    A/C sensor is damaged or the PCM has failed
     

    Trouble Code: P1464



    A/C Demand Out of Self-Test Range

    Possible Causes:



    A/C switch was left "on" during the KOER self-test
     
    A/C PWR circuit is shorted to power (N/C WAC relay contacts)
     
    ACCS circuit is shorted to power
     
    A/C Demand Switch, WAC relay or CCRM is damaged
     

    Trouble Code: P1469



    Low A/C Cycling Period

    Possible Causes:



    Cycling pressure switch circuit open between pin 41 (ACCS) and the PCM, or the IGN RUN circuit is open to the cycling pressure switch circuit (if applicable)
     
    Mechanical A/C system concern (i.e., low refrigerant charge, damaged A/C switch)
     

    Trouble Code: P1473



    Fan Secondary High with Fan(s) Off

    Possible Causes:



    Power-to-Cooling fan circuit open in the wiring harness
     
    Power-to-Cooling fan circuit shorted to power in wiring harness
     
    Cooling fan motor windings open, or fan ground circuit is open
     
    VLCM is damaged or has failed
     

    Trouble Code: P1474



    Hydraulic Cooling Fan Primary Circuit Malfunction

    Possible Causes:



    FC circuit is open or shorted to power
     
    LFC circuit is open or shorted to power (CCRM models)
     
    FC or LFC relay VPWR circuit is open (Start/Run on Probe)
     

    Trouble Code: P1477



    Medium Fan Control Primary Circuit Malfunction

    Possible Causes:



    MFC circuit is open
     
    MFC relay circuit to IGN START/RUN is open
     
    MFC relay is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1479



    High Fan Control Primary Circuit Malfunction

    Possible Causes:



    HFC circuit is open
     
    HFC circuit is shorted to ground
     
    HFC relay power circuit (VPWR) is open
     
    High speed FC relay is damaged or it has failed
     
    PCM has failed
     

    Trouble Code: P1481



    Fan Secondary Low With High Fan On

    Possible Causes:



    High speed cooling fan circuit is open
     
    High speed cooling fan circuit is shorted to ground
     
    High speed cooling fan relay power circuit (VPWR) is open
     
    High speed FC relay is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1483



    Power To Fan Circuit Over-Current Detected

    Possible Causes:



    Power-to-Cooling Fan circuit shorted to ground
     
    Cooling fan motor is damaged or has failed
     
    VLCM is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1500



    VSS Signal Or POSM Signal Intermittent

    Possible Causes:



    VSS pins damaged, loose or pushed in at the connector
     
    VSS circuit open or shorted in the wiring harness (insulation)
     
    VSS wiring harness routing incorrect or VSS mounting incorrect
     
    TSB 01-21-13 contains a repair procedure for this trouble code
     

    Trouble Code: P1501



    VSS Signal Out Of Self-Test Range

    Possible Causes:



    VSS signal is noisy due to Radio Frequency Interference/ Electro-Magnetic Interference (RFI/EMI) from outside devices (ignition wires, charging circuit or aftermarket devices)
     

    Trouble Code: P1502



    VSS Signal Intermittent

    Possible Causes:



    VSS+ or VSS- harness circuit is open
     
    TCSS signal or TCSS signal return harness circuit is open
     
    VSS harness circuit, TCSS harness circuit is shorted to ground
     
    VSS harness circuit, CSS harness circuit is shorted to power
     
    VSS circuit open between the PCM and related control module
     
    VSS or TCSS, or wheel speed sensors circuits are damaged
     
    Modules connected to VSC/VSS harness circuits are damaged
     
    Mechanical drive mechanism for the VSS or TCSS is damaged
     

    Trouble Code: P1504



    Idle Air Control Circuit Malfunction

    Possible Causes:



    IAC circuit is open, shorted to ground or to the VPWR circuit
     
    IAC solenoid VPWR circuit is open
     
    IAC valve is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1505



    Idle Air Control System At Adaptive Clip

    Possible Causes:



    Base engine air leaks are present
     
    Air cleaner element is dirty, plugged or restricted
     
    Throttle body/linkage is binding
     
    IAC valve body is damaged or contaminated
     
    Throttle body is damaged
     

    Trouble Code: P1506



    Idle Air Control Overspeed Error

    Possible Causes:



    Base engine vacuum leaks present
     
    EVAP system has a problem
     
    IAC circuit shorted to ground
     
    IAC valve is stuck open, or it is damaged
     
    Throttle body or throttle plate is contaminated or very dirty
     

    Trouble Code: P1507



    Idle Air Control Underspeed Error

    Possible Causes:



    Air inlet is plugged or the air filter element is severely clogged
     
    IAC circuit is open, or shorted to the VPWR circuit
     
    IAC circuit VPWR circuit is open
     
    IAC solenoid is damaged or has failed
     
    Throttle body or throttle plate is contaminated or very dirty
     

    Trouble Code: P1512



    Intake Manifold Runner Control System Malfunction

    Possible Causes:



    Leaky vacuum reservoir, vacuum lines loose or damaged
     
    Vacuum solenoid or vacuum actuator is damaged
     
    IMRC actuator cable/gears are seized, or the cables are improperly routed or seized
     
    IMRC housing return springs are damaged or disconnected
     
    Lever/shaft return stop may be obstructed or bent, or the lever/shaft wide open stop may be obstructed or bent, or the IMRC lever/shaft may be sticking, binding or disconnected
     
    IMRC control circuit open, shorted or the VPWR circuit is open
     
    PCM has failed
     

    Trouble Code: P1513



    Intake Manifold Runner Control Malfunction (Bank 1)

    Possible Causes:



    IMRC actuator cable/gears are seized, or the cables are improperly routed or seized
     
    IMRC control circuit open, shorted or the VPWR circuit is open
     
    IMRC housing return springs are damaged or disconnected
     
    Leaky vacuum reservoir, vacuum lines loose or damaged
     
    Lever/shaft return stop may be obstructed or bent, or the lever/shaft wide open stop may be obstructed or bent, or the IMRC lever/shaft may be sticking, binding or disconnected
     
    Vacuum solenoid or vacuum actuator is damaged
     
    PCM has failed
     

    Trouble Code: P1516



    Intake Manifold Runner Control Input Error (Bank 1)

    Possible Causes:



    IMRC mechanical fault - the linkage may be bound or seized
     
    Inspect for binding or improper routing. The cable core wire at the IMRC/IMSC housing attachment must have slack and lever must contact close plate stop screw
     

    Trouble Code: P1517



    Intake Manifold Runner Control Input Error (Bank 2)

    Possible Causes:



    IMRC mechanical fault - the linkage may be bound or seized
     
    Visually inspect for binding or improper routing. The cable core wire at the IMRC or IMSC housing attachment must have slack and lever must contact close plate stop screw
     

    Trouble Code: P1518



    Intake Manifold Runner Control Malfunction (Stuck Open)

    Possible Causes:



    IMRC monitor signal circuit shorted to power ground
     
    IMRC Monitor signal circuit shorted to signal ground (return)
     
    IMRC actuator is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1519



    Intake Manifold Runner Control Stuck Closed

    Possible Causes:



    IMRC monitor signal circuit shorted to power ground
     
    IMRC Monitor signal circuit shorted to signal ground (return)
     
    IMRC actuator is damaged or has failed (e.g., there may be a small leak in the vacuum diaphragm of the actuator)
     
    PCM has failed
     

    Trouble Code: P1520



    Intake Manifold Runner Control Input Error

    Possible Causes:



    IMRC control circuit is open or shorted to ground
     
    IMRC Monitor VREF circuit is open
     
    IMRC is damaged or the PCM has failed
     

    Trouble Code: P1530



    Air Conditioning Clutch Circuit Malfunction

    Possible Causes:



    A/C Clutch power circuit open or shorted to VPWR in harness
     
    A/C clutch ground circuit is open
     
    A/C clutch is open
     
    VLCM is damaged or has failed
     

    Trouble Code: P1537



    Intake Manifold Runner Control Malfunction (Bank 1 Stuck Open)

    Possible Causes:



    IMRC monitor signal circuit shorted to power ground
     
    IMRC Monitor signal circuit shorted to signal ground (return)
     
    IMRC actuator is damaged or the PCM has failed
     

    Trouble Code: P1538



    Intake Manifold Runner Control Stuck Open (Bank 2)

    Possible Causes:



    IMRC monitor signal circuit shorted to power ground
     
    IMRC Monitor signal circuit shorted to signal ground (return)
     
    IMRC actuator is damaged or has failed
     
    PCM has failed
     

    Trouble Code: P1539



    Power To A/C Clutch Circuit Over-Current

    Possible Causes:



    A/C Clutch power circuit open or shorted to VPWR in harness
     
    A/C clutch ground circuit is open
     
    A/C clutch is open
     
    VLCM is damaged or has failed
     

    Trouble Code: P1550



    Power Steering Pressure Switch Circuit Malfunction

    Possible Causes:



    PSP switch circuit open or shorted, or the ground circuit open
     
    Steering wheel was not rotated during the KOER Self-Test
     
    PCM has failed
     

    Trouble Code: P1572



    Brake Pedal Switch Circuit Malfunction

    Possible Causes:



    BPP or BPA switches are out of adjustment (one or both)
     
    Blown fuse to switch power circuit
     
    BPP switch or BPA switch is damaged (one or both)
     
    BPP or BPA switch circuit is open or shorted
     
    PCM has failed
     

    Trouble Code: P1605



    PCM Keep Alive Memory Test Error

    Possible Causes:



    Battery terminals loose or corroded (high resistance in circuit)
     
    Keep Alive Memory circuit to PCM interrupted or open
     
    Reprogramming function not performed
     
    PCM has failed
     

    Trouble Code: P1633



    PCM Keep Alive Memory Voltage Too Low

    Possible Causes:



    KAPWR circuit has been interrupted (this problem may be an intermittent condition)
     
    PCM has failed
     

    Trouble Code: P1635



    Tire Axle/Ratio Out Of Acceptable Range

    Possible Causes:



    Incorrect tire size or Incorrect axle ratio
     
    Incorrect VID configuration parameters
     
    PCM need to be reprogrammed
     
    TSB 02-23-4 contains repair information for this trouble code
     

    Trouble Code: P1636



    Inductive Signature Chip Communication Error

    Possible Causes:



    PCM has failed and needs to be replaced
     

    Trouble Code: P1639



    Vehicle ID Block Not Programmed Or Is Corrupt

    Possible Causes:



    PCM may not be the correct application
     
    PCM may need to be reprogrammed
     
    VID configuration may not be correct
     
    TSB 02-23-4 contains repair information for this trouble code
     

    Trouble Code: P1640



    PCM Trouble Codes Available In Another Module

    Possible Causes:



    Trouble codes are stored in a secondary module, which in turn, requested that the PCM turn on the MIL when this code is set.
     

    Trouble Code: P1650



    Power Steering Pressure Switch Circuit Malfunction

    Possible Causes:



    Steering wheel must be turned during the KOER Self-Test
     
    PSP switch/shorting bar is damaged
     
    PSP signal circuit is open or shorted to ground
     
    PSP switch ground (return) circuit is open
     
    PCM has failed
     

    Trouble Code: P1651



    Power Steering Pressure Switch Circuit Malfunction

    Possible Causes:



    Steering wheel must be turned during the KOER Self-Test
     
    PSP switch/shorting bar is damaged
     
    PSP signal circuit is open or shorted to ground
     
    PSP switch ground (return) circuit is open
     
    PCM has failed
     

    Trouble Code: P1700



    Transaxle Mechanical Malfunction

    Possible Causes:



    This code can set due to low transmission fluid level
     
    Refer to the appropriate Transmission Repair Manual or information in electronic media to perform a complete diagnosis of the automatic transmission when this code is set
     

     
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