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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 >> B1638-Right Hi Beam Control Circuit High >> Diagnostic Test
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Diagnostic Test

  1. INTERMITTENT CONDITION 
    1. Turn the ignition on.
    2. Using the scan tool, clear all FCM DTCs.
    3. Turn the Headlamps on.
    4. With the scan tool read the DTC information.

      Does the scan tool read: B1638-RIGHT HI BEAM CONTROL CIRCUIT HIGH?

      Yes 

      • Go to step  2

      No 

  2. RIGHT HIGH BEAM BULB 
    1. Turn the ignition off.
    2. Inspect the Right High Beam Bulb Assembly.

      Is the inoperative bulb OK?

      Yes 

      • Go to step  3

      No 

  3. (L34) HIGH BEAM CONTROL CIRCUIT 
    Fig 1: Checking High Beam Control Circuit
    GC0120085Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the FCM C2 harness connector.
    3. Measure the resistance of the (L34) High Beam Control circuit.

      Is the resistance above 5.0 Ohms?

      Yes 

      No