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Home >> Jeep >> 2009 >> Commander Overland, RWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Memory Modules >> Front Control Module (FCM) - Electrical Diagnostics >> DTC Troubleshooting >> B1820-Hood Ajar Input Circuit High >> Diagnostic Test
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Diagnostic Test

  1. TEST FOR INTERMITTENT CONDITION 
    NOTE: Open the hood and ensure the Hood Ajar Switch is connected before proceeding
    1. Using the scan tool, record and erase DTCs
    2. Close the hood.
    3. Cycle the ignition from on to off.
    4. Turn the ignition on.
    5. Open then close the hood.
    6. Using the scan tool, read DTCs.

      Does the scan tool display B1820-HOOD AJAR INPUT CIRCUIT HIGH?

      Yes 

      • Go to step  2

      No 

  2. INCORRECT HOOD AJAR SWITCH INSTALLED 
    1. Inspect the retainer ring on the hood ajar switch.
    2. A dark brown retainer ring identifies the hood ajar switch used for certain export applications, while a white retainer ring identifies the remote starter system application.

      Is the correct switch installed?

      Yes 

      • Go to step  3

      No 

  3. HOOD AJAR SWITCH OPEN 
    1. Disconnect the Hood Ajar Switch harness connector.
    2. Measure the resistance between the two terminals of the Hood Ajar Switch

      Is the resistance approximately 1000 Ohms?

      Yes 

      • Go to step  4

      No 

  4. (Z384) GROUND CIRCUIT OPEN 
    Fig 1: Checking Ground Circuit Open
    GC0120123Courtesy of CHRYSLER LLC
    1. Using a 12-volt Test Light connected to 12-volts, check the (Z384) Ground circuit.

      Does the test light illuminate?

      Yes 

      • Go to step  5

      No 

  5. (G70) HOOD AJAR SWITCH SENSE CIRCUIT SHORT TO VOLTAGE 
    Fig 2: Checking Hood AJAR Switch Sense Circuit Short To Voltage
    GC0120124Courtesy of CHRYSLER LLC
    1. Disconnect the Front Control Module 49-way connector.
    2. Turn the ignition on.
    3. Measure the voltage between the (G70) Hood Ajar Switch Sense circuit and ground.

      Is there any voltage present?

      Yes 

      No 

      • Go to step  6
  6. (G70) HOOD AJAR SWITCH SENSE CIRCUIT OPEN 
    Fig 3: Checking Hood AJAR Switch Sense Circuit Open
    GC0120125Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Integrated Power Module C2 40-way connector.
    3. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the IPM connector and the Hood Ajar Switch connector.

      Is the resistance below 2.0 Ohms?

      Yes 

      • Go to step  7

      No 

  7. (G70) IPM HOOD AJAR SWITCH SENSE CIRCUIT OPEN 
    Fig 4: Checking Integrated Power Module Hood AJAR Switch Sense Circuit Open
    GC0120126Courtesy of CHRYSLER LLC
    NOTE: Use the graphic connector pinout as a reference to check the Integrated Power Module.
    1. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the IPM C2 40-connector and the Front Control Module 49-way connector.

      Is the resistance below 1.0 Ohm?

      Yes 

      No