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Home >> Jeep >> 2009 >> Commander Overland, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> Ignition System >> Front Control Module (FCM) - Electrical Diagnostics >> DTC Troubleshooting >> B1634-Left 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: B1634-LEFT HI BEAM CONTROL CIRCUIT HIGH?

      Yes 

      • Go to step  2

      No 

  2. LEFT HIGH BEAM BULB 
    1. Turn the ignition off.
    2. Inspect the Left High Beam Bulb Assembly.

      Is the inoperative bulb OK?

      Yes 

      • Go to step  3

      No 

  3. (L33) HIGH BEAM CONTROL CIRCUIT 
    Fig 1: Checking High Beam Control Circuit
    GC0120081Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the FCM C2 harness connector.
    3. Measure the resistance of the (L33) High Beam Control circuit.

      Is the resistance above 5.0 Ohms?

      Yes 

      No