Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read DTCs and record on the repair order.
2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 10.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
VISUALLY INSPECT CATALYTIC CONVERTER
1. Inspect the Catalytic Converter for the following damage:
  - Damage Catalytic Converter, dents or holes.
  - Severe discoloration caused by overheating the Catalytic Converter.
  - Catalytic Converter broke internally.
  - Inspect both ends of the converter, inlet and outlet.
  - Leaking Catalytic Converter.
  Were any problems found?
  
  Yes
  - Repair the condition that may have caused the failure and replace the Catalytic Converter in accordance with the Service Information. Refer to CONVERTER, CATALYTIC, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (K902) O2 SENSOR 1/1 RETURN CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/1 harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (K902) O2 Sensor 1/1 Return circuit in the O2 Sensor 1/1 harness connector.
  Is the voltage at 2.5 volts?
  
  Yes
  - Go To 4
  No
  - Go To 5
CHECK THE (K904) O2 SENSOR 1/2 RETURN CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/2 harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (K904) O2 Sensor 1/2 Return circuit in the O2 Sensor 1/2 harness connector.
  Is the voltage at 2.5 volts?
  
  Yes
  - Go To 10
  No
  - Go To 7
CHECK THE (K902) O2 SENSOR 1/1 RETURN CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Check for continuity between ground and the (K902) O2 Sensor 1/1 Return circuit in the O2 Sensor 1/1 harness connector.
  Is there continuity between ground and the (K902) O2 Sensor 1/1 Return circuit?
  
  Yes
  - Repair the (K902) O2 Sensor 1/1 Return circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK THE (K902) O2 SENSOR 1/1 RETURN CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K902) O2 Sensor 1/1 Return circuit from the O2 Sensor 1/1 harness connector to the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 9
  No
  - Repair the (K902) O2 Return Upstream circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (K904) O2 SENSOR 1/2 RETURN CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/2 harness connector.
3. Check for continuity between ground and the (K904) O2 Sensor 1/2 Return circuit in the O2 Sensor 1/2 harness connector.
  Is there continuity between ground and the (K904) O2 Sensor 1/2 Return circuit?
  
  Yes
  - Repair the (K904) O2 Sensor 1/2 Return circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
CHECK THE (K904) O2 SENSOR 1/2 RETURN CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K904) O2 Sensor 1/2 Return circuit from the O2 Sensor 1/2 harness connector to the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 9
  No
  - Repair the (K904) O2 Sensor 1/2 Return circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE EXHAUST SYSTEM FOR LEAKS
1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .
  Were any exhaust leaks found?
  
  Yes
  - Repair or replace the leaking exhaust parts as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 11
CHECK THE ENGINE MECHANICAL CONDITION
1. Check the exhaust for excessive smoke caused by an internal problem in the engine.
  Is an engine mechanical condition present?
  
  Yes
  - Repair the engine mechanical condition as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 12
CHECK FOR AN AGING UPSTREAM O2 SENSOR AND NEW DOWNSTREAM O2 SENSOR
NOTE:
Check for contaminants that may have damaged the O2 Sensor and Catalytic Converter: contaminated fuel, unapproved silicone, oil and coolant, repair necessary.
1. A new Downstream O2 Sensor along with an aging Upstream O2 Sensor may cause the DTC to set.
2. Review the vehicles repair history.
  Has the Downstream O2 Sensor been replaced without replacing the Upstream O2 Sensor?
  
  Yes
  - Replace the Upstream O2 Sensor in accordance with the Service Information. Refer to SENSOR, OXYGEN, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 13
INSTALL A NEW CATALYTIC CONVERTER
If there are no possible causes remaining, view repair.

Repair
- Replace the Catalytic Converter in accordance with the Service Information. Refer to CONVERTER, CATALYTIC, REMOVAL AND INSTALLATION .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .