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Diagnostic Test

  1. 1) ACTIVE DTC 

    Start the engine and allow it to reach normal operating temperature.

    WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

    With a scan tool, select View DTCs.

    Is the DTC Active at this time? 

    Yes 

    1. Go To  2).

    No 

    1. Refer to INTERMITTENT CONDITION Diagnostic Procedure.
  2. 2) GENERATOR OPERATION 
    Fig 1: Probing Generator Field Control Circuit At Generator Field Harness Connector
    GC0050942Courtesy of CHRYSLER LLC

    Disconnect the Generator harness connector.

    Using a 12-volt test light connected to ground, probe the (K125) Generator Field Control circuit in the Generator Field harness connector.

    Ignition on, engine not running.

    NOTE: The DTC needs to be cleared before actuating the Solenoid, if the DTC is not cleared, the Solenoid may not be allowed to actuate.

    With a scan tool, actuate the Generator Field Driver.

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

    Yes 

    1. Replace the Generator.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  3).
  3. 3) (K125) GEN FIELD CIRCUIT SHORTED VOLTAGE 
    Fig 2: Checking Generator Field Circuit For Short To Voltage
    GC0050945Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C2 PCM harness connector.

    Ignition on, engine not running.

    Measure the voltage on the (K125) Gen Field Control circuit in the Generator Field harness connector.

    Is there any voltage present? 

    Yes 

    1. Repair the short to voltage in the (K125) Gen Field Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  4).
  4. 4) (K125) GEN FIELD CIRCUIT OPEN 
    Fig 3: Checking Generator Field Control Circuit For Open
    GC0050943Courtesy of CHRYSLER LLC

    Turn the ignition off.

    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 (K125) Gen Field Control circuit from the Generator Field harness connector to appropriate terminal of the special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To  5).

    No 

    1. Repair the open in the (K125) Gen Field Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  5. 5) (K125) GEN FIELD CIRCUIT SHORTED TO GROUND 
    Fig 4: Checking Generator Field Control Circuit For Short To Ground
    GC0050944Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (K125) Gen Field Control circuit in the Generator Field harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (K125) Gen Field Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  6).
  6. 6) PCM 
    NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

    Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

    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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