Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Dodge Pickup and 2004 Dodge Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Refer to VERIFICATION TESTS for appropriate verification test procedures.

Ignition on, engine not running.
Record all DTCs and the related Freeze Frame data.

Check for any related TSBs.

Using a 12-volt test light connected to ground, backprobe the (K20) Gen Field Control circuit at the back of the Generator.

With the DRBIII®, actuate the Generator Field Driver.

Does the test light blink?
1. Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
  Perform POWERTRAIN VERIFICATION TEST VER - 3 .
2. No --> Go To 2
Ignition on, engine not running.
Carefully inspect all connectors for corrosion or spread terminals before continuing.

Backprobe the (K125) Generator Field Source circuit at back of Generator with a volt meter.

With the DRBIII® actuate the Generator Field Driver.

Is the voltage above 10.0 volts?
1. Yes --> Go To 3
2. No --> Repair the open in the (K125) Gen Field Source circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 3 .
Turn the ignition off.
Disconnect the PCM harness connectors.

Disconnect the Generator Field harness connector.

Measure the resistance of the (K20) Generator Field Control circuit from the Generator Field harness connector to the PCM harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 4
2. No --> Repair the open in the (K20) Gen Field Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 3 .
Measure the resistance between ground and the (K20) Generator Field Control circuit in the PCM harness connector.
Is the resistance below 100 ohms?
1. Yes --> Repair the short to ground in the (K20) Gen Field Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 3 .
2. No --> Go To 5.
Measure resistance across the Generator Field Terminals at the Generator.
Is the resistance between 0.5 of and ohm and 15 ohms?
1. Yes --> Go To 6
2. No --> Repair the Generator as necessary.
  Perform POWERTRAIN VERIFICATION TEST VER - 3 .

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.
If there are no possible causes remaining, view repair.
1. Repair
  1. Replace and program the Powertrain Control Module per Service Information.
  2. Perform POWERTRAIN VERIFICATION TEST VER - 3 .