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Home >> Dodge and Ram >> 2009 >> Durango Base, 3.7 K >> Repair and Diagnosis >> Engine Performance >> Ignition System >> (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. With 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. With 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. Depress the plunger of the hood ajar switch and measure the resistance between the two terminals of the switch.

      Is the resistance approximately 1k ohms?

      Yes 

      • Go to step  4

      No 

  4. (Z926) GROUND CIRCUIT OPEN 
    Fig 1: Checking Ground Circuit For Open
    GC0097824Courtesy of CHRYSLER LLC
    1. Using a 12-volt Test Light connected to 12-volts, check the (Z926) 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
    GC0097825Courtesy of CHRYSLER LLC
    1. Disconnect the FCM 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
    GC0106185Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Measure the resistance of the (G70) Hood Ajar Switch Sense circuit between the FCM 49-way connector and the Hood Ajar Switch connector.

      Is the resistance below 2.0 ohms?

      Yes 

      No