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Home >> Chrysler >> 2009 >> Sebring Limited, 2D Convertible >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P0573 To P0643 - NGC >> P0591-Speed Control Switch 2 Performance >> Diagnostic Test
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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.
    - 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
    NOTE: This DTC is a two trip fault. If the scan tool indicates a one trip failure, the possible cause may have been the customer pressing both switches simultaneously. Test drive the vehicle and activate the Speed Control system. If the DTC matures to an active fault a repair is necessary.
    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
    GC0099572Courtesy 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 (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be above 4.8 Volts with the Speed Control Switch removed.
    5. 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.
    6. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be below 0.2 of a Volt with the jumper wire in place.

      Is the (V72) S/C Signal 2 voltage above 4.8 Volts with the Speed Control Switch removed and below 0.2 of a Volt with the jumper wire in place?

      Yes 

      No 

      • Go to step  3
  3. SPEED CONTROL SWITCH WIRING HARNESS 
    1. Turn the ignition off.
    2. Disconnect the C8 Clockspring harness connector.
    3. Turn the ignition on.
    4. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The voltage should be above 4.8 Volts with the C8 Clockspring connector disconnected.
    5. Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit at the C8 Clockspring connector, not at the harness connector.
    6. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be below 0.2 of a Volt with the jumper wire in place.

      Are the Speed Control voltages displayed as described?

      Yes 

      No 

      • Go to step  4
  4. CLOCKSPRING 
    Fig 2: Checking S/C Circuit
    GC0099977Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the C2 Clockspring harness connector.
    3. Turn the ignition on.
    4. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The voltage should be above 4.8 Volts with the connector disconnected.
    5. Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the C2 Clockspring harness connector.
    6. With a scan tool, read the (V72) S/C Signal 2 voltage.
      NOTE: The (V72) S/C Signal 2 voltage should be below 0.2 of a Volt with the jumper wire in place.

      Are the Speed Control voltages displayed as described?

      Yes 

      No 

      • Go to step  5
  5. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE 
    Fig 3: Measuring Voltage On S/C Switch Sense Circuit In Clockspring C2 Harness Connector
    GC0094914Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Powertrain Control Module (PCM) C3 harness connector.
    3. Turn the ignition on.
    4. 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. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO GROUND 
    Fig 4: Measuring Resistance Between Ground And (V72) S/C Switch Sense 2 Circuit In Clockspring C2 Harness Connector
    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  7

      No 

  7. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO THE (V937) S/C SWITCH GROUND CIRCUIT 
    Fig 5: Measuring Resistance Between S/C Switch Sense Circuit And S/C Switch Return Circuit In Clockspring C2 Harness Connector
    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  8

      No 

  8. (V72) S/C SIGNAL 2 CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 6: Measuring Resistance Of S/C Switch Sense 2 Circuit From Clockspring Harness Connector To Appropriate Terminal Of PCM Pinout Box 8815
    GC0094917Courtesy of CHRYSLER LLC
    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 PCM Pinout Box 8815 to perform diagnosis.
    1. Measure the resistance of the (V72) S/C Signal 2 circuit between the Clockspring C2 harness connector and the appropriate terminal of PCM Pinout Box 8815.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  9

      No 

  9. (V937) S/C SWITCH GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 7: Measuring Resistance Of S/C Switch Return Circuit From Clockspring C2 Harness Connector To Appropriate Terminal Of PCM Pinout Box 8815
    GC0094912Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (V937) S/C Switch Ground circuit between the Clockspring C2 harness connector and the appropriate terminal of PCM Pinout Box 8815.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  10

      No 

  10. 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).
    2. Look for any chafed, pierced, pinched, or partially broken wires.
    3. Verify that there is good pin to terminal contact in the Switch and Powertrain Control Module connectors.
    4. Look for broken, bent, pushed out or corroded terminals.
    5. Perform any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No 

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