Diagnostic Test

WARNING: This page is about a different car, the 2024 Jeep Grand Wagoneer L and 2024 Jeep Grand Wagoneer. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR OTHER DTC'S
1. Turn the ignition on.
2. With the scan tool, check the PCM for LIN Bus or System Voltage related DTC's.
  Are there any LIN Bus or System Voltage related DTCs?
  
  Yes
  - Repair other DTCs before continuing.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 2
ALTERNATOR B+ CIRCUIT
1. Turn the ignition off.
2. Using a 12-volt test light connected to ground, probe the B+ circuit at the generator.
  Does the test tight illuminate as brightly as a direct connection to the Battery?
  
  Yes
  - Go To 3
  No
  - Repair the Alternator B+ circuit for an open.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK ALTERNATOR DRIVE BELT
1. Visually inspect the generator drive belt for glazing, cracks and other problems.
2. Inspect the generator drive belt and tensioner for proper tension.
  Were any problems found?
  
  Yes
  - Repair or replace as necessary.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
TEST DRIVE THE VEHICLE
1. Turn the ignition on.
2. With the scan tool, erase DTC's.
3. Test drive the vehicle.
4. With the scan tool, read DTC's.
  Does the scan tool display this DTC?
  
  Yes
  - Replace the Alternator in accordance with the service information.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .