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Home >> Jeep >> 2023 >> Grand Cherokee Laredo, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 36 (Hybrid Control Processor Module (HCP) - Environmental Data Diagnosis And Verification Test) >> Environmental Data Diagnosis >> Internal Fault >> Diagnostic Test
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Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR DTC TO RETURN 
    WARNING:

    On vehicles equipped with the high voltage system, you must thoroughly read and follow all High Voltage Safety procedures. In addition, before performing any diagnostic or service procedure near a high voltage component, you must perform the High Voltage Power Down. Failure to follow these instructions may result in possible serious or fatal injury.

    Read the HIGH VOLTAGE SAFETY PROCEDURES. Refer to:  HIGH VOLTAGE SAFETY PROCEDURES  . 

    When the HIGH VOLTAGE POWER DOWN PROCEDURE is necessary. Refer to:  HIGH VOLTAGE POWER DOWN  . 

    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  2

    No 

  2. CHECK FOR OTHER HIGH VOLTAGE DTCS 
    1. Refer to the recorded DTCs.

      Are there any High Voltage DTCs set in the PCM, HCP, BPCM, ABM and IDCM

      Yes 

      No 

      • Go To  3
  3. CHECK CONTACTOR STATUS IN THE BATTERY PACK CONTROL MODULE (BPCM) 
    1. With the scan tool, check the HV contactor status in the BPCM.

      Are all of the HV contactors closed?

      Yes 

      • Go To  4

      No 

  4. CHECK THE HIGH VOLTAGE DATA IN THE BATTERY PACK CONTROL MODULE (BPCM) AND ELECTRIC A/C COMPRESSOR (EAC) 
    1. With the scan tool, read the High Voltage data in the BPCM AND EAC.
      NOTE:

      Make sure that the EAC Fuse is not open.

      Are the voltages equal to each other?

      Yes 

      • Go To  5

      No 

  5. ELECTRIC A/C COMPRESSOR (EAC) 
    1. Reconnect any previously disconnected wire harness connections and prepare the vehicle for power up.
    2. Turn the ignition on, not in ready mode.
    3. Using the scan tool, record current DTCs and environmental data and erase EAC DTCs.
    4. Turn the ignition off. Wait one minute.
    5. Turn the ignition on. Wait one minute.
    6. Using the scan tool, read DTCs.

      Does the scan tool display this DTC as active?

      Yes 

      No