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Diagnostic Test

  1. ACTIVE DTC 
    1. Start the engine and allow it to reach normal operating temperature.
      WARNING:

      When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

      NOTE:

      Diagnose and repair any system voltage or sensor supply voltage DTCs before continuing with this test.

    2. With the scan tool, select View DTCs.

      Is the DTC Active at this time

      Yes 

      • Go To  2

      No 

  2. CHECK THE (N7) FTP SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE 
    Fig 1: Checking FTP Signal Circuit For A Short To Voltage
    GC0106775Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the FTP Sensor harness connector.
    3. Turn the ignition on.
    4. Measure the voltage on the (N7) FTP Signal circuit at the FTP harness connector.

      Is there any voltage reading above 5.2 volts?

      Yes 

      • Repair the (N7) FTP Signal circuit for a short to voltage.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  3
  3. CHECK THE (N7) FTP SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the PCM C1 harness connector.
      CAUTION:

      Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.

    3. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
    4. Measure the resistance of the (N7) FTP Signal circuit between the FTP harness connector and the GPEC Adaptor.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  4

      No 

      • Repair the (N7) FTP Signal circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. CHECK FOR THE (N7) FTP SIGNAL CIRCUIT SHORTED TO THE (K859) 5-VOLT SUPPLY CIRCUIT 
    Fig 2: Checking FTP Signal Circuit For A Short To The 5-Volt Supply Circuit
    GC0106776Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance between the (N7) FTP Signal circuit and the (K859) 5-Volt Supply circuit at the FTP harness connector.

      Is the resistance above 10k Ohms?

      Yes 

      • Go To  5

      No 

      • Repair the short between the (K859) 5-Volt Supply circuit and the (N7) FTP Signal circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK THE SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Measure the resistance of the (K917) Sensor Ground circuit from the FTP harness connector to the appropriate terminal the GPEC Adaptor.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  6

      No 

  6. FTP SENSOR 
    Fig 3: Checking FTP Sensor Circuit
    GC0106774Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Reconnect the PCM C1 harness connector.
    3. Connect a jumper between the (N7) FTP Signal circuit and the (K917) Sensor Ground circuit in the Sensor harness connector.
    4. Turn the ignition on.
    5. With the scan tool, monitor the FTP voltage.
      NOTE:

      The sensor voltage should be approximately 0.0 volts (plus or minus 0.1 volts) with the jumper in place.

      Does the scan tool display the voltage as described above?

      Yes 

      • Verify that there is good pin to terminal contact in the FTP and Powertrain Control Module connectors. Replace the FTP if no problems were found with the connectors.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  7
  7. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the FTP and the Powertrain Control Module (PCM).
    2. Look for any chafed, pierced, pinched or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the FTP and Powertrain Control Module connectors.
    4. Perform any Technical Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      No