Diagnostic Test

CHECK FOR ANY SERVICE BULLETINS OR PCM SOFTWARE UPDATES
1. Check for any applicable Service Bulletins or Flash updates related to the DTC.
  Are there any applicable Service Bulletins or Flash updates?
  
  Yes
  - Perform the applicable repair.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 2
CHECK FOR OTHER DTCS
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) 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.
  Are there any PCR Control Relay Control circuit or Charging system DTCs present?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DTC TROUBLESHOOTING .
  No
  - Go To 3
CHECK THE PCR CONTROL RELAY (T760) OUTPUT CIRCUIT FOR VOLTAGE AT THE POWER CONTROL RELAY
1. Turn the ignition off.
2. Disconnect the Power Control Relay C1 harness connector.
3. Turn the ignition on, engine not running.
4. Measure the voltage on the PCR Control Relay (T760) Output circuit at the Power Control Relay C1 harness connector.
  NOTE:
  There should be no voltage present since the Power Control Relay is only energized during an auto start event.
  
  Is there any voltage present?
  
  Yes
  - Go To 4
  No
  - Go To 5
CHECK THE PCR CONTROL RELAY (T760) OUTPUT CIRCUIT FOR A SHORT TO ANOTHER VOLTAGE SUPPLY CIRCUIT AT THE PDC CONNECTOR
1. Turn the ignition off.
2. Disconnect the Power Distribution Center (PDC) harness connector.
3. Check for continuity between the PCR Control Relay (T760) Output circuit and all other circuits at the PDC harness connector.
  Is there continuity between the PCR Control Relay (T760) Output circuit and any other circuit?
  
  Yes
  - Repair the PCR Control Relay (T760) Output circuit for a short to the circuit that showed continuity.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Power Distribution Center in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK FOR THE POWER CONTROL RELAY STUCK ON (OPEN)
NOTE:
There should be direct continuity between the two posts on the normally closed Power Control Relay if the relay is not energized and functioning properly.
1. Start the engine and allow it to idle.
2. Measure the voltage at the Power Control Relay C2 post.
3. Measure the voltage at the Power Control Relay C3 post.
  NOTE:
  The voltage measured should be equal to the charging system output voltage at both posts.
  
  Is the voltage equal to the charging system at both posts?
  
  Yes
  - Go To 6
  No, the voltage at both posts is equal to the Auxiliary Battery voltage:
  - Go To 13
  No, the voltage at the post on the Main Battery side is equal to the charging system output and the voltage at the post on the Auxiliary Battery side is equal to the Auxiliary Battery voltage:
  - Replace the Power Control Relay in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE AUXILIARY BATTERY POSITIVE AND NEGATIVE CABLE CONNECTIONS
1. Check for a proper connection between the Battery posts and cable ends at the Auxiliary Battery.
  NOTE:
  There should be no voltage drop between the posts and cable ends.
  
  Is there a good connector between the posts and cable ends?
  
  Yes
  - Go To 7
  No
  - Clean the Battery Cables and posts and retest.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE FUSES AND PDC CONNECTIONS
1. Check the Fuse(s) that feed the PCM Fused B+ circuit.
2. Check the Auxiliary Battery cable connection at the PDC for a proper connection.
  Were any issues found with the fuses or connections?
  
  Yes
  - Make the necessary repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
CHECK FOR HIGH RESISTANCE IN THE AUXILIARY BATTERY CABLE
1. Perform a voltage drop on the Auxiliary Battery Positive cable between the Auxiliary Battery Positive Cable End and the Power Control Relay.
2. Perform a voltage drop on the Auxiliary Battery Positive cable between the Auxiliary Battery Positive Cable End and the connection at the PDC.
  Does the Auxiliary Battery Positive Cable have a voltage drop between the Auxiliary Battery and Power Control Relay or PDC?
  
  Yes
  - Repair or replace the Auxiliary Battery Positive Cable.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 9
CHECK AUXILIARY BATTERY NEGATIVE CABLE AND GROUND LOCATION
1. Check the Auxiliary Battery Negative Cable for a proper ground at the ground location.
2. Perform a voltage drop on the Auxiliary Battery Negative Cable between the Auxiliary Battery Negative Cable End and the ground location.
  Is the Negative Battery Cable grounded properly?
  
  Yes
  - Go To 10
  No
  - Repair or replace the Auxiliary Battery Negative Cable or ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE AUXILIARY BATTERY STATE OF CHARGE
1. Disconnect the Negative Cable from both Batteries.
2. Use the (special tool #GR8-1220KIT-CHRY, AGM Battery Tester/Charger Station) or equivalent to load test the Auxiliary Battery.
  Did the Auxiliary Battery pass the load test?
  
  Yes
  - Go To 11
  No
  - Recharge or replace the Auxiliary Battery and retest.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK (A209) FUSED B+ SUPPLY VOLTAGE TO THE PCM
1. Disconnect the PCM C1 harness connector.
2. Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the PCM harness connector. Reconnect the PCM C1 harness connector in-line with the GPEC Adaptor connected in-line.
3. Turn the ignition on.
4. Measure the voltage on the (A209) Fused B+ circuit at the GPEC Adaptor.
5. Measure the voltage of the Auxiliary Battery.
  Is the voltage on the (A209) Fused B+ circuit within 0.2 volts of the Auxiliary Battery?
  
  Yes
  - Go To 12
  No
  - Repair the (A209) Fused B+ circuit for high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all PCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. 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.
6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. 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 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 POWER CONTROL RELAY FUSE IN THE BATTERY DISTRIBUTION UNIT (FUSE ARRAY)
1. Check the Power Control Relay Fuse in the Battery Distribution Unit (Fuse Array) for continuity.
  Is the Fuse open?
  
  Yes
  - Replace the open fuse and check the related wiring harnesses and circuits for any conditions that could cause the open fuse.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 14
CHECK FOR HIGH RESISTANCE IN THE MAIN BATTERY CABLE BETWEEN THE MAIN BATTERY AND THE POWER CONTROL RELAY
1. Perform a voltage drop on the Main Battery Positive cable between the Main Battery Positive Cable End and the Power Control Relay.
  Does the Main Battery Positive Cable have a voltage drop between the Main Battery and Power Control Relay?
  
  Yes
  - Repair or replace the Main Battery Positive Cable.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Check the wiring between the Alternator and Main Battery for excessive voltage drop in the circuitry.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .