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.
With the DRBIII®, read DTCs and record the related Freeze Frame data.

NOTE: If P0031 and P0051 are set along with P0136, inspect the related fuse and repair as necessary.

Is the Good Trip Counter displayed and equal to zero?
1. Yes --> Go To 2
2. No --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure).
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
Turn the ignition off.
Remove the Heater Relay from the PDC.

Measurement is taken at the Heater Relay component.

Measure the resistance of the O2 Sensor Heater Relay Coil.

Is the resistance above 100 ohms?
1. Yes --> Replace the O2 Sensor Heater Relay.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 3
Ignition on, engine not running.
With the DRBIII®, actuate the ASD Relay.

Using a 12-volt test light connected to ground, probe the (A141) Fused ASD Relay Output circuit of the O2 Heater Relay in the PDC.

Does the test light illuminate brightly when the relay actuates?
1. Yes --> Go To 4
2. No --> Repair the open or short to ground in the (A141) ASD Relay Output circuit. Inspect the related fuse and repair as necessary.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
Turn the ignition off.
Disconnect the PCM harness connectors.

Measure the resistance of the (K127) O2 Heater Relay Control circuit from the PDC (Heater Relay) connector to the PCM harness connector.

Is the resistance below 5.0 ohms?
1. Yes --> Go To 5
2. No --> Repair the open in the (K127) O2 Heater Relay Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
Measure the resistance between ground and the (K127) O2 Heater Relay Control circuit at the PDC connector.
Is the resistance below 100 ohms?
1. Yes --> Repair the short to ground in the (K127) O2 Sensor Heater Relay Control circuit.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 6
Turn the ignition off.
NOTE: Allow the O2 Sensor to cool to room temperature.

Disconnect the 1/2 and 2/2 O2 Sensor harness connectors.

Measure the resistance across each of the O2 Sensor Heater elements, component side.

NOTE: O2 Heater Element resistance values should be measured at 70°F (21.1°C). The resistance value will vary with different temperature values.

Is the resistance of the O2 Sensor Heater Elements between 2.0 and 30.0 ohms?
1. Yes --> Go To 7
2. No --> Replace the O2 Sensor.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .

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 not possible causes remaining, view repair.
1. Repair
  1. Replace and program the Powertrain Control Module per Service Information.
  2. Perform POWERTRAIN VERIFICATION TEST VER - 5 .