Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
This DTC does not necessarily indicate an overcharging condition. It merely indicates that the Alternator Sense is greater than the Alternator output back to the Battery and PDC.
1. Start the engine.
2. Allow the idle to stabilize.
3. With the scan tool, read the active DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE CONDITION OF THE BATTERY
NOTE:
Inspect the vehicle for aftermarket accessories that may exceed the Alternator System output.
1. Use the (special tool #GR8-1220KIT-CHRY, AGM Battery Tester/Charger Station) or equivalent to load test the Battery.
  Did the Battery pass or fail?
  
  Passed
  - Go To 3
  Failed
  - Perform the appropriate repair according to the Battery tester.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE ALTERNATOR OUTPUT
1. With the scan tool, navigate to data display and monitor the target charging voltage.
2. Using a voltmeter, measure the voltage at the Alternator output stud.
  NOTE:
  The voltage reading at the Alternator output stud should be within 0.2 volts of the target charging voltage.
  
  Are the voltage readings within 0.2 volts of each other?
  
  Yes
  - Go To 4
  No
  - Replace the Alternator in accordance with the Service Information. Refer to GENERATOR, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE ALTERNATOR OUTPUT CIRCUIT AND SYSTEM VOLTAGE
1. Using a voltmeter, measure the voltage at the Fused B+ circuit at the PDC B+ terminal.
  NOTE:
  Compare the voltage reading to the voltage at the Alternator output stud.
  
  Is the voltage within 0.2 volts of the measurement at the Alternator output stud?
  
  Yes
  - Go To 5
  No
  - Repair the open or excessive resistance in the Alternator output circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE PDC
1. Turn the ignition off.
2. Back probe the (A908) Fused B+ circuit at the PDC C2 harness connector.
3. Start the engine and allow it to idle.
4. Using a voltmeter, measure the voltage at the (A908) Fused B+ circuit.
  NOTE:
  Compare the voltage reading to the voltage at the Alternator output stud.
  
  Is the voltage within 0.2 volts of the measurement at the Alternator output stud?
  
  Yes
  - Go To 6
  No
  - Check the fuse and terminals for signs of a spread terminal, corrosion or high resistance. If no problems are found, replace the PDC in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (A908) FUSED B+ CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
  CAUTION:
  Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
3. Connect the (special tool #10436, Adapter, GPEC Diagnostic) in line with the GPEC Adaptor.
4. Turn the ignition on.
5. Using a voltmeter, measure the voltage at the (A908) Fused B+ circuit at the GPEC Adaptor.
  NOTE:
  Compare the voltage reading to the voltage at the Alternator output stud. Approximately 2.0 Ohms of resistance in this circuit can drop the voltage by approximately 0.5 volts.
  
  Is the voltage within 0.2 volts of the measurement at the Alternator output stud?
  
  Yes
  - Go To 7
  No
  - Repair the (A908) Fused B+ circuit for 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 (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
  - Repair the poor connections.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .