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Diagnostic Test

  1. 1) PRETEST 
    NOTE: Diagnose and repair any BCM Ignition MUX or IPM Ignition Run-Start Mismatch DTC's before proceeding with this test.

    Turn the ignition off.

    Remove and inspect Fuse #30 in the IPM.

    If fuse is open, replace with proper rated fuse.

    Remove the Starter Relay from the IPM.

    Turn the ignition to the Start position for at least 5 seconds.

    Turn the ignition off.

    Remove and inspect Fuse #30 in the IPM.

    Is IPM Fuse #30 open? 

    Yes 

    1. Go To step  2).

    No 

    1. Go To step  5).
  2. 2) (T751) IGNITION SWITCH OUTPUT (START) CIRCUIT SHORT TO GROUND - IPM 
    Fig 1: Measuring The Resistance Between Ground And The Ignition Switch Output Circuit
    GC0048757Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the IPM harness C4 connector.

    Disconnect the Ignition Switch harness connector.

    Measure the resistance between ground and the (T751) Ignition Switch Output (Start) circuit.

    Is the resistance below 5 ohms? 

    Yes 

    1. Repair the (T751) Ignition Switch Output (Start) circuit for a short to ground between the IPM and the Ignition Switch.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Go To step  3).
  3. 3) (T751) IGNITION SWITCH OUTPUT (START) CIRCUIT SHORT TO GROUND - PCM 
    Fig 2: Measuring The Resistance Between Ground And The Ignition Switch Output Circuit Between The IPM And The PCM
    GC0048758Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the IPM C7 harness connector.

    Disconnect the PCM harness connector.

    Measure the resistance between ground and the (T751) Ignition Switch Output (Start) circuit between the IPM and the PCM.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the (T751) Ignition Switch Output (Start) circuit for a short to ground between the IPM and the PCM.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Go To step  4).
  4. 4) IPM INTERNAL SHORT 
    Fig 3: Ignition Switch Harness Connector And IPM C4 Harness Connector
    GC0048759Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Reconnect the Ignition Switch harness connector.

    Reconnect the IPM C4 harness connector.

    Install proper rated fuse to IPM Fuse #30.

    Turn the ignition to the Start position for at least 5 seconds.

    With the scan tool, read DTCs.

    Did this DTC reset? 

    Yes 

    1. Replace the IPM in accordance with the Service Information.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. The condition is not present at this time. Monitor scan tool parameters while wiggling the related wire harness. Refer to any Technical Service Bulletins (TSB) that may apply. Visually inspect the related wiring harness and connector terminals.
    2. Perform BODY VERIFICATION TEST - VER 1 .
  5. 5) IPM INTERNAL OPEN 
    Fig 4: Measuring The Voltage Of The Ignition Switch Output Circuit While Holding The Ignition Switch In The Start Position
    GC0048760Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the IPM C4 harness connector.

    Measure the voltage of the (T751) Ignition Switch Output (Start) circuit while holding the Ignition Switch in the Start position.

    Does the test light illuminate brightly? 

    Yes 

    1. Replace the IPM in accordance with the Service Information.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Go To step  6).
  6. 6) (T751) IGNITION SWITCH OUTPUT (START) CIRCUIT OPEN 
    Fig 5: Measuring The Resistance Of The Ignition Switch Output Circuit Between The IPM C4 Connector And The Ignition Switch Connector
    GC0048761Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the IPM C4 harness connector.

    Disconnect the Ignition Switch harness connector.

    Measure the resistance of the (T751) Ignition Switch Output (Start) circuit between the IPM C4 connector and the Ignition Switch connector.

    Is the resistance above 5.0 ohms? 

    Yes 

    1. Repair the (T751) Ignition Switch Output (Start) circuit for an open.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Go To step  7).
  7. 7) IGNITION SWITCH 

    Turn the ignition off.

    Disconnect the IPM C4 harness connector.

    While back probing, measure the voltage of the (T751) Ignition Switch Output (Start) circuit while holding the Ignition switch in the Start position.

    Is the voltage below 10.5 volts? 

    Yes 

    1. Replace the Ignition Switch in accordance with the Service Information.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. The condition is not present at this time. Monitor scan tool parameters while wiggling the related wire harness. Refer to any Technical Service Bulletins (TSB) that may apply. Visually inspect the related wiring harness and connector terminals.
    2. Perform BODY VERIFICATION TEST - VER 1 .
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