Diagnostic Test

VISUALLY INSPECT THE ALTERNATOR AND BELT
NOTE:
Inspect and test the Battery with the Midtronics Battery Tester or equivalent for a shorted or dead cell before continuing with this test.

NOTE:
Inspect the vehicle for aftermarket accessories that may exceed the Alternator System output.

NOTE:
If the P0622 DTC is also present, diagnose and repair that DTC before continuing with this test procedure.

NOTE:
Inspect the fusible link in the charge wire or fuses in the PDC depending on application. If an open fusible link or fuse is found, use the wire diagram/schematic as a guide and inspect the wiring and connectors for damage.
1. Turn the ignition off.
2. Inspect the Alternator belt and Tensioner for proper size and operation.
3. Check for proper belt routing installation.
  Are the belt and tensioner installed properly and functioning correctly?
  
  Yes
  - Go To 2
  No
  - Perform the appropriate repair.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE ALTERNATOR OUTPUT AT THE ALTERNATOR OUTPUT STUD
1. Start the engine.
2. Hold the engine speed above 1157 rpm.
3. With the scan tool, navigate to data display and monitor the target charging voltage.
4. Using a voltmeter, measure the voltage at the Alternator output stud.
  Is the Alternator output more than 1.0 volt below the target charging voltage?
  
  Yes
  - Verify that there is good pin to terminal contact in the Alternator connector. If no problems are found, replace the Alternator. Refer to GENERATOR, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK THE ALTERNATOR OUTPUT AT THE PCM
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 adapter in line with the PCM C1 harness connector.
  (special tool #10436, Adapter, GPEC Diagnostic)
4. Start the engine.
5. Hold the engine speed above 1157 rpm.
6. With the scan tool, navigate to data display and monitor the target charging voltage.
7. Measure the voltage on the (A209) Fused B+ circuit at the GPEC Adaptor.
  Is the (A209) Fused B+ circuit voltage more than 1.0 volt below the target charging voltage?
  
  Yes
  - Repair the (A209) Fused B+ circuit for high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
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 POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .