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.

Check for any related TSBs.
Ignition on, engine not running.

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

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 .
Inspect the Catalytic Converter for the following damage.
Damaged Catalytic Converter, dent and holes.

Severe discoloration caused by overheating the Catalytic Converter.

Catalytic Converter broken internally.

Leaking Catalytic Converter.

Were any problems found?
1. Yes --> Replace the Catalytic Converter. Repair the condition that may have caused the failure.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 3
Start Engine and let idle.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.

Check for exhaust leaks between the engine and the appropriate downstream O2 Sensor.

Is there any exhaust leaks?
1. Yes --> Repair or replace leaking exhaust parts as necessary.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 4
Check the exhaust for excessive smoke from internal oil or coolant leaks.
Is there an oil or coolant consumption condition present?
1. Yes --> Repair engine mechanical condition as necessary and replace Catalytic Converter.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 5
Turn the ignition off.
NOTE: A new Downstream O2 Sensor along with an aging Upstream O2 Sensor may cause this trouble code to set.

Review vehicle repair history.

Has the Downstream O2 Sensor been replaced without replacing the Upstream O2 Sensor?
1. Yes --> Replace the appropriate Upstream Oxygen Sensor.
  Perform POWERTRAIN VERIFICATION TEST VER - 5 .
2. No --> Go To 6
If there are no possible causes remaining, view repair.
1. Repair
  1. Replace the Catalytic Converter.
  2. Perform POWERTRAIN VERIFICATION TEST VER - 5 .