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Diagnostic Test

  1. DIAGNOSTIC TROUBLE CODE (DTC) IS ACTIVE 
    NOTE: Refer to the following table when diagnosing speed control switch voltage DTCs.
    Application Switch 1 voltage  Switch 2 voltage 
    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
    1. 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 may result in possible serious or fatal injury.
      NOTE: It may be necessary to test drive the vehicle and operate the speed control in order for this DTC to set.
    2. With a scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go to step  2

      No 

  2. SPEED CONTROL SWITCH 
    Fig 1: Checking S/C Circuit
    GC0099974Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Remove the Speed Control Switch in accordance with the Service Information.
    3. Turn the ignition on.
    4. With a scan tool, read the (V71) S/C Signal 1 and (V72) S/C Signal 2 voltages.
      NOTE: The voltages should be above 4.8 Volts with the Speed Control Switch connector disconnected.
    5. 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.
    6. With a scan tool, read the (V71) S/C Signal 1 voltage.
      NOTE: The (V71) S/C Signal 1 voltage should be below.2 of a Volt with the jumper wire in place.
    7. Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the Speed Control Switch harness connector.
    8. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be below.2 of a Volt with the jumper wire in place.

      Are the Speed Control voltages displayed as described?

      Yes 

      No 

      • Go to step  3
  3. CLOCKSPRING 
    Fig 2: Checking S/C Circuit
    GC0099975Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Clockspring C2 connector.
    3. Turn the ignition on.
    4. With a scan tool, read the (V71) S/C Signal 1 and (V72) S/C Signal 2 voltages.
      NOTE: The voltages should be above 4.8 Volts with the connector disconnected.
    5. Connect a jumper wire between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the Clockspring C2 harness connector.
    6. With a scan tool, read the (V71) S/C Signal 1 voltage.
      NOTE: The (V71) S/C Signal 1 voltage should be below.2 of a Volt with the jumper wire in place.
    7. Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the Clockspring C2 harness connector.
    8. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be below.2 of a Volt with the jumper wire in place.

      Are the Speed Control voltages displayed as described?

      Yes 

      No 

      • Go to step  4
  4. (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO VOLTAGE 
    Fig 3: Measuring Voltage Of (V71) S/C Switch Sense 1 Circuit In Clockspring C2 Harness Connector
    GC0094907Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Powertrain Control Module (PCM) harness connector.
    3. Turn the ignition on.
    4. Measure the voltage of the (V71) S/C Signal 1 circuit in the Clockspring C2 harness connector.

      Is there any voltage present?

      Yes 

      No 

      • Go to step  5
  5. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE 
    Fig 4: Checking S/C Switch Signal Circuit
    GC0094914Courtesy of CHRYSLER LLC
    1. Measure the voltage of the (V72) S/C Signal 2 circuit in the Clockspring C2 harness connector.

      Is there any voltage present?

      Yes 

      No 

      • Go to step  6
  6. (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO GROUND 
    Fig 5: Checking S/C Circuit
    GC0094908Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Measure the resistance between ground and the (V71) S/C Signal 1 circuit in the Clockspring C2 harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go to step  7

      No 

  7. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO GROUND 
    Fig 6: Checking S/C Circuit
    GC0094915Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Measure the resistance between ground and the (V72) S/C Signal 2 circuit in the Clockspring C2 harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go to step  8

      No 

  8. (V71) S/C SIGNAL 1 CIRCUIT SHORTED TO THE (V937) S/C SWITCH GROUND CIRCUIT 
    Fig 7: Checking S/C Circuit
    GC0094909Courtesy of CHRYSLER LLC
    1. Measure the resistance between the (V71) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the C2 Clockspring harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go to step  9

      No 

  9. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO THE (V937) S/C SWITCH GROUND CIRCUIT 
    Fig 8: Checking S/C Circuit
    GC0094916Courtesy of CHRYSLER LLC
    1. Measure the resistance between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the Clockspring C2 harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go to step  10

      No 

  10. (V71) S/C SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 9: Checking S/C Circuit
    GC0099972Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (V71) S/C Signal 1 circuit between the Clockspring C2 harness connector and the Powertrain Control Module (PCM) harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  11

      No 

  11. (V72) S/C SIGNAL 2 CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 10: Checking S/C Circuit
    GC0099976Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (V72) S/C Signal 2 circuit between the Clockspring C2 harness connector and the Powertrain Control Module (PCM) harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  12

      No 

  12. (V937) S/C SWITCH GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 11: Checking S/C Circuit
    GC0099973Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (V937) S/C Switch Ground circuit between the Clockspring C2 harness connector and the Powertrain Control Module (PCM) harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  13

      No 

  13. POWERTRAIN CONTROL MODULE (PCM) 
    1. 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.
      • Perform any technical service bulletins that may apply.

      Were any problems found?

      Yes 

      No