Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR OTHER DTCS
1. Turn Ignition on.
2. Using the scan tool, check for DTCs and record on the repair order.
  Is the P0622 DTC active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to 3.2L - DIAGNOSTIC CODE INDEX .
  No
  - Go To 2
CHECK THE ALTERNATOR AND BELT FOR DEFECTS
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:
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 3
  No
  - Perform the appropriate repair.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
CHECK THE ALTERNATOR OUTPUT AT THE ALTERNATOR OUTPUT STUD
1. Hold the engine speed above 1157 RPM.
2. With the scan tool, navigate to data display and monitor the target charging voltage.
3. Using a voltmeter, measure the voltage at the Alternator output stud.
  Is the Alternator output more than 1.0 volts below the target charging voltage?
  
  Yes
  - Verify that there is good pin to terminal contact in the Alternator connector. If OK, replace the Alternator. Refer to GENERATOR, REMOVAL, 3.2L .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - Go To 4
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 (special tool #10436, Adapter, GPEC Diagnostic) in line with the PCM C1 harness connector.
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. Using a voltmeter, measure the voltage on the (A209) Fused B+ circuit at the GPEC Adaptor.
  Is the (A209) Fused B+ circuit voltage more than 1.0 volts below the target charging voltage?
  
  Yes
  - Repair the (A209) Fused B+ circuit for excessive resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - Go To 5
CHECK THE POWERTRAIN CONTROL MODULE (PCM) POWERS AND GROUNDS FOR PROPER OPERATION
1. Perform the CHECKING THE PCM POWERS AND GROUNDS test procedure. Refer to CHECKING THE PCM POWER AND GROUND CIRCUITS .
2. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Alternator and the Powertrain Control Module (PCM).
3. Look for any chafed, pierced, pinched, or partially broken wires.
4. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Alternator and the Powertrain Control Module connectors.
5. Perform any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - Go To 6
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, 2.4L/3.2L .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 3.2L . .