Diagnostic Test
- CHECK FOR AN ACTIVE DTC
- With the scan tool, read DTCs and Freeze Frame Data and record on the repair order.
- With the scan tool, erase DTCs.
- Using the recorded Freeze Frame Data and the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
- 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 .
- CHECK THE VOLTAGE SUPPLY TO STARTER RELAY 1
- Turn the ignition off.
- Remove Starter Relay 1 from the Auxiliary PDC.
- Using a 12 volt test light connected to ground, probe the Fused B+ circuit at Starter Relay 1 connector (pin 30) in the PDC.
- Attempt to crank the engine with the ignition key.NOTE:
The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the Battery.
Is the test light illuminated and bright?
Yes
- Go To 7
No
- Go To 3
- CHECK THE VOLTAGE SUPPLY TO STARTER RELAY 1 FROM BCM
- Turn the ignition on.
- Using a 12 volt test light connected to ground, probe the (F30) Fused B+ circuit at the BCM.NOTE:
The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the Battery.
Is the test light illuminated and bright?
Yes
- Go To 4
No
- Go To 6
- ISOLATE AND CHECK THE (F30) FUSED B+ CIRCUIT FOR A SHORT TO GROUND
- The ignition must be off when checking a circuit for continuity to ground.
- Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit.
- Connect the negative lead of the DVOM to a known good ground.
- With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
NOTE:There should be no continuity between ground and the circuit being tested.
Is there continuity between ground and the circuit being tested?
Yes
- Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 5
- CHECK THE (F30) FUSED B+ CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Measure the resistance of the (F30) Fused B+ circuit between the BCM C3 harness connector and the Starter Relay 1 connector (pin 30) in the PDC.
Is the resistance below 3.0 Ohms?
Yes
- Go To 6
No
- Repair the (F30) Fused B+ circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance of the (F30) Fused B+ circuit between the BCM C3 harness connector and the Starter Relay 1 connector (pin 30) in the PDC.
- CHECK RELATED BCM AND COMPONENT CONNECTIONS
- Disconnect all BCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- 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.
- Reconnect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Replace and program the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL AND INSTALLATION .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
No
- The wiring or poor connection problem has been repaired.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- CHECK THE (T750) STARTER RELAY OUTPUT CIRCUIT FOR A SHORT TO GROUND
- Turn the ignition off.
- Disconnect the PCM C1 harness connector.
- Disconnect the Starter C2 harness connector.
- Check for continuity between ground and the (T750) Starter Relay Output circuit at the Starter Relay 1 connector (pin 87) in the PDC.
Is there continuity between ground and the (T750) Starter Relay Output circuit?
Yes
- Repair the (T750) Starter Relay Output circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 8
- CHECK THE (T750) STARTER RELAY OUTPUT CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Measure the resistance of the (T750) Starter Relay Output circuit -
- between the PCM C1 harness connector and the Starter Relay 1 connector (pin 87) in the PDC.
- between the Starter C2 harness connector and the Starter Relay 1 connector (pin 87) in the PDC.
Is the resistance below 3.0 Ohms for both legs of the circuit?
Yes
- Go To 9
No
- Repair the (T750) Starter Relay Output circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance of the (T750) Starter Relay Output circuit -
- REPLACE STARTER RELAY 1 AND RETEST FOR DTC
- Replace Starter Relay 1.
- Reconnect the PCM C1 harness connector.
- Attempt to crank the engine with the ignition key.
Did the DTC return?
Yes
- Go To 10
No
- Replacing Starter Relay 1 repaired the fault.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK RELATED PCM AND COMPONENT CONNECTIONS
- Perform any Service Bulletins that apply.
- Disconnect all PCM harness connectors.
- Disconnect all related in-line harness connections (if equipped).
- Disconnect the related component harness connectors.
- 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.
- Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
- Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
- Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
- With the scan tool, erase DTCs.
- Test drive or operate the vehicle in accordance with the when monitored and set conditions.
- 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 .