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Diagnostic Test

  1. 1) SPEED CONTROL VENT CONTROL 

    Ignition on, engine not running.

    With the scan tool, select View DTCs and record the related Freeze Frame data.

    With the scan tool, actuate the Speed Control Vent Solenoid and note operation.

    Does the Speed Control Vent Solenoid actuate properly? 

    Yes 

    1. Refer to INTERMITTENT CONDITION Diagnostic Procedure.

    No 

    1. Go to  2).
  2. 2) (V30) S/C BRAKE SWITCH OUTPUT CIRCUIT 
    Fig 1: Checking Speed Control Brake Switch Output Circuit
    GC0027163Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the S/C Servo harness connector.

    Ignition on, engine not running.

    Using the scan tool, actuate the S/C Vent Solenoid.

    Using a test light connected to ground, probe the (V30) S/C Brake Switch Output circuit in the S/C Servo harness connector.

    Does the test light illuminate brightly and flash on and off? 

    Yes 

    1. Go to  5).

    No 

    1. Go to  3).
  3. 3) (V32) S/C SUPPLY CIRCUIT 
    Fig 2: Checking Speed Control Brake Switch Supply Circuit
    GC0027164Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Connect the S/C Servo harness connector.

    Disconnect the Stop Lamp Switch harness connector.

    Ignition on, engine not running.

    Using the scan tool, actuate the S/C Vent Solenoid.

    Using a test light connected to ground, probe the (V32) S/C Supply circuit in the Stop Lamp Switch harness connector.

    Does the test light illuminate brightly? 

    Yes 

    1. Go to  4).

    No 

    1. Go to  8).
  4. 4) (Z384) S/C GROUND CIRCUIT OPEN 
    Fig 3: Checking Speed Control Ground Circuit For Open
    GC0002977Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the S/C Servo harness connector.

    Measure the resistance of the (Z384) S/C Ground circuit at the S/C Servo harness connector to ground.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  5).

    No 

    1. Repair the open in the (Z384) S/C Ground circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  5. 5) SPEED CONTROL VENT SOLENOID 
    Fig 4: Checking Speed Control Vent Solenoid
    GC0002986Courtesy of CHRYSLER LLC

    Ignition on, engine not running.

    With the scan tool, actuate the Speed Control Vent Solenoid.

    Using a 12-volt test light connected to battery voltage, probe the (V36) S/C Vent Control circuit.

    Does the test light illuminate brightly and flash on and off? 

    Yes 

    1. Replace the Speed Control Servo.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  6).
  6. 6) (V35) S/C VENT CONTROL CIRCUIT OPEN 
    Fig 5: Checking Speed Control Vent Control Circuit For Open
    GC0002985Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C3 PCM harness connector.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (V35) S/C Vent Sol Control circuit from the Speed Control Servo harness connector to the appropriate terminal of special tool # 8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  7).

    No 

    1. Repair the open/high resistance in the (V35) S/C Vent Sol Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  7. 7) (V35) SPEED CONTROL VENT SOLENOID CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 6: Checking Speed Control Vent Solenoid Control Circuit For Short To Ground
    GC0002984Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (V35) S/C Vent Solenoid Control circuit at the Speed Control Servo harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (V35) S/C Vent Sol Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  10).
  8. 8) (V32) S/C SUPPLY OPEN 
    Fig 7: Checking Speed Control Brake Switch Supply Circuit For Open
    GC0027165Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C3 PCM harness connector.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (V32) S/C Supply circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  9).

    No 

    1. Repair the open/high resistance in the (V32) S/C Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  9. 9) (V32) S/C SUPPLY CIRCUIT SHORTED TO GROUND 
    Fig 8: Checking Speed Control Brake Switch Supply Circuit For Short To Ground
    GC0027146Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (V32) S/C Supply circuit at the Speed Control Servo harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (V32) S/C Supply circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go to  10).
  10. 10) PCM 
    NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
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