Diagnostic Test

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

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Turn the ignition on.
6. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .
CHECK THE (K372) EXHAUST GAS TEMPERATURE CATALYST SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Exhaust Gas Temperature Catalyst Sensor harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance between ground and the (K372) Exhaust Gas Temperature Catalyst Sensor Signal circuit at the Exhaust Temperature Catalyst Sensor harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (K372) Exhaust Gas Temperature Catalyst Sensor Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
CHECK THE (K372) EXHAUST GAS TEMPERATURE CATALYST SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE (K900) SENSOR GROUND
1. Measure the resistance between the (K372) Exhaust Gas Temperature Catalyst Sensor Signal circuit and the (K900) Sensor Ground circuit at the Exhaust Gas Temperature Catalyst Sensor harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the short between the (K372) Exhaust Gas Temperature Catalyst Sensor Signal circuit and the (K900) Sensor Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
CHECK THE ABILITY OF THE PCM TO READ THE EXHAUST GAS TEMPERATURE CATALYST SENSOR INPUT
1. Connect the Exhaust Gas Temperature Catalyst Sensor harness connector.
2. Connect the PCM C1 harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Turn the ignition off for 75 seconds.
6. Disconnect the Exhaust Gas Temperature Catalyst Sensor harness connector.
7. Turn the ignition on.
8. With the scan tool, read DTCs.
  Does the DTC P0428 become active?
  
  Yes
  - Replace the Exhaust Gas Temperature Catalyst Sensor in accordance with the service information. Refer to SENSOR, EXHAUST TEMPERATURE, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Go To 5
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 (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Repair the poor connections.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .