Diagnostic Test

1) ACTIVE DTC
Start the engine and allow it to reach 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.

Increase engine speed by pressing the accelerator pedal. Do not exceed 3500 RPM.

With the 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) GENERATOR OPERATION

Fig 1: Probing Generator Field Control Circuit At Generator Field Harness Connector
Courtesy of CHRYSLER LLC

Turn the ignition off.

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.

NOTE: The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery.

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

Yes
1. Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors. If OK, replace the Generator.
2. Perform POWERTRAIN VERIFICATION TEST .
No
1. Go to 3).
3) (K125) GEN FIELD CIRCUIT SHORTED TO VOLTAGE

Fig 2: Checking Generator Field Circuit For Short To Voltage
Courtesy 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) (K125) GEN FIELD CIRCUIT OPEN

Fig 3: Checking Generator Field Control Circuit For Open
Courtesy 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) (K125) GEN FIELD CIRCUIT SHORTED TO GROUND

Fig 4: Checking Generator Field Control Circuit For Short To Ground
Courtesy 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) POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors.

Refer to any Technical Service Bulletins that may apply.

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 .