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Diagnostic Test

  1. 1) DTC IS ACTIVE 
    NOTE: Refer to the following table when diagnosing speed control switch voltage DTCs.
    - Switch 1 Voltage (pin A27)  Switch 2 Voltage (pin A26) 
    On/Off - Min. 0.5882 3.5294
    On/Off - Max. 1.1373 3.9216
    Set - Min. 3.1569 1.1765
    Set - Max. 3.5686 1.5686
    Cancel - Min. 1.5882 2.8431
    Cancel - Max. 2.0000 3.2549
    Accel - Min. 3.8824 2.0392
    Accel - Max. 4.1765 2.4706

    Start the engine and allow it to idle for at least 60 seconds.

    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 can result in personal injury or death.
    NOTE: It may be necessary to test drive the vehicle and operate the speed control in order for this DTC to set.

    With a scan tool, select View DTCs.

    Is the status Active for this DTC? 

    Yes 

    1. Go to  2).

    No 

    1. Refer to the *CHECKING FOR AN INTERMITTENT CONDITION Diagnostic Procedure.
  2. 2) SPEED CONTROL SWITCH 
    Fig 1: Connecting Jumper Wire Between S/C Signal 1 Circuit And S/C Switch Ground Circuit In Control Switch Harness Connector
    GC0054096Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Remove the Speed Control Switch in accordance with the Service Information.

    Turn the ignition on.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The (V71) S/C Signal 1 voltage should be above 4.8 volts with the Speed Control Switch removed.

    Connect a jumper wire between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the Speed Control Switch harness connector.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The (V71) S/C Signal 1 voltage should be below .2 volts with the jumper wire in place.

    Is the (V71) S/C Signal 1 voltage above 4.8 volts with the Speed Control Switch removed and below .2 volts with the jumper wire in place? 

    Yes 

    1. Replace the Speed Control Switch in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  3).
  3. 3) CLOCKSPRING 

    Turn the ignition off.

    Disconnect the Steering Control Module (SCM) C5 harness connector.

    Turn the ignition on.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The voltage should be above 4.8 volts with the Steering Control Module (SCM) C5 connector disconnected.

    Connect a jumper wire between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit at the Steering Control Module (SCM) C5 connector, not at the harness connector.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The (V71) S/C Signal 1 voltage should be below .2 volts with the jumper wire in place.

    Are the Speed Control voltages displayed as described? 

    Yes 

    1. Replace the Clockspring in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  4).
  4. 4) STEERING CONTROL MODULE (SCM) 
    Fig 2: Connecting Jumper Wire Between S/C Signal 1 Circuit And S/C Switch Ground Circuit In SCM C2 Harness Connector
    GC0054097Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Steering Control Module (SCM) C2 connector.

    Turn the ignition on.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The voltage should be above 4.8 volts with the connector disconnected.

    Connect a jumper wire between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the Steering Control Module (SCM) C2 harness connector.

    With a scan tool, read the (V71) S/C Signal 1 voltage.

    NOTE: The (V71) S/C Signal 1 voltage should be below .2 volts with the jumper wire in place.

    Are the Speed Control voltages displayed as described? 

    Yes 

    1. Replace the Steering Control Module (SCM) in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  5).
  5. 5) (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO VOLTAGE 
    Fig 3: Measuring Voltage Of (V71) S/C Signal 1 Circuit In The Steering Control Module (SCM) Harness Connector
    GC0054098Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Powertrain Control Module (PCM) connector.

    Turn the ignition on.

    Measure the voltage of the (V71) S/C Signal 1 circuit in the Steering Control Module (SCM) harness connector.

    Is there any voltage present? 

    Yes 

    1. Repair the (V71) S/C Signal 1 circuit for a short to voltage.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  6).
  6. 6) (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO GROUND 
    Fig 4: Measuring Resistance Between Ground And S/C Signal 1 Circuit In SCM C2 Harness Connector
    GC0054212Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance between ground and the (V71) S/C Signal 1 circuit in the Steering Control Module (SCM) harness connector.

    Is the resistance above 100 ohms? 

    Yes 

    1. Go to  7).

    No 

    1. Repair the (V71) S/C Signal 1 circuit for a short to ground.
    2. Perform PCM VERIFICATION TEST .
  7. 7) (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO THE (V937) S/C SWITCH GROUND CIRCUIT 
    Fig 5: Checking S/C Signal 1 Circuit For Short To S/C Switch Ground Circuit
    GC0054213Courtesy of CHRYSLER LLC

    Measure the resistance between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the Steering Control Module (SCM) harness connector.

    Is the resistance above 100 ohms? 

    Yes 

    1. Go to  8).

    No 

    1. Repair the (V71) S/C Signal 1 circuit for a short to the Steering Control Module (SCM) circuit.
    2. Perform PCM VERIFICATION TEST .
  8. 8) (V71) S/C SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 6: Checking S/C Signal 1 Circuit For Open Or High Resistance
    GC0054099Courtesy of CHRYSLER LLC

    Measure the resistance of the (V71) S/C Signal 1 circuit between the Steering Control Module (SCM) harness connector and the Powertrain Control Module (PCM) harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  9).

    No 

    1. Repair the (V71) S/C Signal 1 circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  9. 9) (V937) S/C SWITCH GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 7: Checking S/C Switch Ground Circuit For Open Or High Resistance
    GC0054100Courtesy of CHRYSLER LLC

    Measure the resistance of the (V937) S/C Switch Ground circuit between the Steering Control Module (SCM) harness connector and the Powertrain Control Module (PCM) harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  10).

    No 

    1. Repair the (V937) S/C Switch Ground circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  10. 10) POWERTRAIN CONTROL MODULE (PCM) 

    Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Speed Control Switch and the Powertrain Control Module (PCM).

    Look for any chafed, pierced, pinched, or partially broken wires.

    Look for broken, bent, pushed out or corroded terminals.

    Refer to any Technical Service Bulletins that may apply.

    Were any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Replace the Powertrain Control Module (PCM) in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .
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