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Home >> Jeep >> 2021 >> Gladiator Mojave, Part Time T/Case Control, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 10 (DRIVEABILITY - Diesel - Non-DTC Based Diagnostics) >> Diagnosis And Testing >> Engine Cranks But Will Not Start >> Diagnostic Test
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Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. PCM CODES PRESENT 
    1. With the scan tool, read the PCM DTCs.

      Does the scan tool display any PCM DTCs?

      Yes 

      • Perform the appropriate PCM DTC procedure.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .

      No 

      • Go To  3
  2. SKIM CODES PRESENT 
    1. With the scan tool, read the SKIM DTCs.

      Does the scan tool display any SKIM DTCs?

      Yes 

      • Refer to DIAGNOSIS AND TESTING and perform the appropriate SKIM DTC procedure.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .

      No 

      • Go To  3
  3. CHECK FOR INTAKE SYSTEM RESTRICTIONS 
    1. Turn the ignition off.
    2. Ensure vehicle has adequate fuel supply in fuel tank.
    3. Inspect all air intake and Turbocharger related hoses/tubes and connections.
    4. Inspect the air filter for excessive dirt, soiling or other problems that may cause restricted air flow.

      Were any problems found?

      Yes 

      • Repair or replace as necessary.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .

      No 

      • Go To  4
  4. ECT SENSOR 
    1. Using a temperature probe, check the vehicle temperature near the ECT Sensor.
    2. Turn the ignition on.
    3. With the scan tool in sensors, read the ECT Sensor temperature.
    4. Compare the temperature probe reading with the scan tool reading.

      Are the two readings within 10°C of each other?

      Yes 

      • Go To  5

      No 

      • Repair as necessary.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .
  5. GLOW PLUGS 
    1. Check the glow plugs for proper operation.

      Are the glow plugs operating properly?

      Yes 

      • Go To  6

      No 

      • Repair as necessary.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .
  6. CHECK THE FUEL DELIVERY SYSTEM 
    1. Perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure. Refer to DIAGNOSIS AND TESTING .

      Is the fuel delivery system operating properly?

      Yes 

      • Repair as necessary.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .

      No 

      • Go To  7
  7. ENGINE DRIVE CHAINS 
    1. Make sure the Engine Drive Chains are installed correctly and the camshaft and crankshaft gears are timed correctly.

      Were any problems found?

      Yes 

      • Repair as necessary.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .

      No 

      • Replace and program the Powertrain Control Module in accordance with the service information.
      • Perform the PCM VERIFICATION TEST. Refer to the appropriate service information .