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.

READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN
1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 10.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To Next Step
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR OTHER DTCS
2. Refer to the recorded DTCs.
  Are there any Camshaft Oil Control Valve Circuit or Slow Response DTCs active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DIAGNOSTIC CODE INDEX .
  No
  - Go To Next Step
CHECK THE ENGINE OIL LEVEL AND CONDITION
NOTE:
The following items should be checked before continuing with this procedure. Failure to do so may lead to misdiagnosis.
- LOW ENGINE OIL LEVEL
- INCORRECT ENGINE OIL FILTER (DOES NOT MEET OEM SPECIFICATIONS)
- DETERIORATED OR DIRTY OIL
- CONTAMINATED ENGINE OIL
- INCORRECT ENGINE OIL VISCOSITY
- AERATED ENGINE OIL
1. If any of the above conditions are found, repair as necessary.
  Were any of the above conditions present?
  
  Yes
  - Repair the engine oiling issue (i.e. low engine oil, incorrect engine oil viscosity, contaminated or deteriorating engine oil, incorrect engine oil filter (DOES NOT MEET OEM SPECIFICATIONS), etc.).
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To the appropriate Service Information
CHECK THE ENGINE OIL PRESSURE AND ENGINE MECHANICAL CONDITION
1. Turn the engine off.
2. Install the applicable adaptor and install an oil pressure gauge to the adaptor. If the adaptor is not available, monitor the oil pressure reading with the scan tool.
3. Start the engine and allow it to idle.
4. Monitor the engine oil pressure reading.
  Is the oil pressure reading steady and above the engine specifications?
  
  Yes
  - Go To Next Step
  No
  - Repair the engine mechanical condition (i.e. improper oil drain back or blocked screen in cylinder head, oil sludge, worn crankshaft main or rod bearings, damaged oil pump, pick-up tube or seal, etc.).
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
REPLACE THE VCT SOLENOID AND RETEST FOR DTC
1. Turn the ignition off.
2. Replace the VCT Solenoid in accordance with the Service Information. Refer to SOLENOID, VALVE TIMING, REMOVAL AND INSTALLATION .
3. Connect the VCT Solenoid harness connector.
4. Turn the ignition on.
5. With the scan tool, erase DTCs.
6. Using the recorded Freeze Frame data and the When Monitored conditions, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To Next Step
  No
  - Replacing the VCT Solenoid/Camshaft Oil Control Valve repaired the fault.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE CAMSHAFT 1/1 TONE WHEEL
1. Turn the ignition off.
2. Check the alignment of the CMP Sensor Tone Wheel on the Camshaft in accordance with the service information.
  Is the CMP Sensor Tone Wheel aligned correctly?
  
  Yes
  - Go To Next Step
  No
  - Replace the Camshaft Assembly in accordance with the Service Information. Refer to CAMSHAFT, ENGINE, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE ENGINE TIMING ALIGNMENT
1. Verify proper alignment of the Timing Chain and gears in accordance with the Service Information. Also check the Timing Chain Tensioner and Guide for faulty or broken components.
  Were any issue found with the timing alignment or components?
  
  Yes
  - Perform the appropriate repair in accordance with the Service Information. The "Cam/Crank Relearn" Procedure must be performed every time there has been a repair/replacement made to a CMP Sensor and/or CKP Sensor, Flywheel, Valvetrain, Timing Chain or gears. Failure to do so can cause a misfire fault to set. With the scan tool, perform the "Cam/Crank Relearn" Procedure.
  No
  - Replace the Cam Phaser Assembly in accordance with the Service Information. Refer to PHASER, CAMSHAFT, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .