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Diagnostic Test

  1. TEST FOR INTERMITTENT CONDITION 
    NOTE: Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.
    1. Turn the ignition on.
      NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.
    2. With the scan tool, select ECU View.
      NOTE: A red "X" will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.
      NOTE: Check the TIPM for any active CAN C hardware and any ignition related DTCs, perform DTCs before proceeding.

      Does the scan tool display a red "X" next to the module?

      Yes 

      • Go to step  2

      No 

      • The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
  2. CHECK ECM POWER AND GROUND 
    1. Check the ECM power and ground circuits.

      Were any problems found?

      Yes 

      No 

      • Go to step  3
  3. (D65) CAN C BUS (+) CIRCUIT OPEN 
    Fig 1: Checking CAN C Bus (+) Circuit
    GC0100531Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the TIPM C3 harness connector.
    3. Disconnect the ECM C1 harness connector.
    4. Measure the resistance of the (D65) CAN C Bus (+) circuit between the TIPM connector and the ECM connector.

      Is resistance below 5.0 ohms?

      Yes 

      • Go to step  4

      No 

  4. (D64) CAN C BUS (-) CIRCUIT OPEN 
    Fig 2: Checking CAN C Bus (-) Circuit
    GC0100532Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (D64) CAN C Bus (-) circuit between the TIPM connector and the ECM connector.

      Is resistance below 5.0 ohms?

      Yes 

      No