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Home >> Jeep >> 2007 >> Commander Overland, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> Ignition System >> Ignition System - Electrical Diagnostics >> Ignition Systems - Electrical Diagnostics >> DTC Troubleshooting >> B2100-Ignition Run/Start Input Circuit Performance >> Diagnostic Test
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Diagnostic Test

  1. 1) CHECK FOR ACTIVE DTC 
    NOTE: If B2104 or B2105 are active, perform those tests first before proceeding.
    NOTE: Check the Junction Block Fuse #24. An open fuse can cause this DTC to set. If open refer to the wiring diagrams to help isolate a possible shorted circuit.

    With the scan tool, read the active DTC's.

    Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 10 seconds.

    With the scan tool, read the active DTC's.

    Does the scan tool display this DTC as active? 

    Yes 

    1. Go to  2).

    No 

    1. If the DTC is stored, check for an intermittent condition. Using the wiring diagram/schematic as a guide, visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
  2. 2) (F942) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN 
    Fig 1: Checking Fused Ignition Switch Output Circuit
    GC0044484Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the IPM C2 connector.

    Turn the ignition on.

    Measure the voltage of the (F942) Fused Ignition Switch Output circuit in the IPM C2 connector.

    Is the voltage above 10.0 volts? 

    Yes 

    1. Go to  3).

    No 

    1. Repair the (F942) Fused Ignition Switch Output circuit for an open.
    2. Perform BODY VERIFICATION TEST .
  3. 3) (F942) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN 
    Fig 2: Checking Fused Ignition Switch Output Circuit
    GC0044485Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Remove the FCM from the Integrated Power Module.

    NOTE: Reconnect the IPM C2 connector.

    Turn the ignition on.

    Measure the voltage of the (F942) Fused Ignition Switch Output circuit in the Front Control IPM connector.

    Is the voltage above 10.0 volts? 

    Yes 

    1. Replace and program the Front Control Module in accordance with the service information.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Replace the Integrated Power Module in accordance with service information.
    2. Perform BODY VERIFICATION TEST .