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Home >> Jeep >> 2021 >> Grand Cherokee Trackhawk >> Repair and Diagnosis >> Engine Performance >> System >> 6.2L - DTCS P0443 To P0688 >> DTC Troubleshooting >> P0606-Internal Control Processor >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    NOTE:

    Diagnose any CMP or CKP Sensor faults before continuing. Check for intermittent loose CMP or CKP connections.

    NOTE:

    Diagnose any repair any low system voltage DTCs before proceeding with test.

    WARNING:

    When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

    1. Turn the ignition on.
    2. With the scan tool, erase DTCs.
    3. Monitor the scan tool for at least two minutes.
    4. Cycle the ignition off and on several times, leaving the ignition on for at least 10 seconds at a time.
    5. Start the engine and allow it to reach operating temperature.
    6. With the scan tool, read DTCs and record on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. POWERTRAIN CONTROL MODULE (PCM) 
    1. Perform any Service Bulletins that may apply.
    2. Using the wiring diagram/schematic as a guide, inspect the Powertrain Control Module (PCM) wiring and connectors.
    3. Look for any chafed, pierced, pinched, or partially broken wires.
    4. Look for broken, bent, pushed out or corroded terminals.

      Were any problems found?

      Yes 

      No 

      • Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .