P0593

P0593-SPEED CONTROL SWITCH 2 CIRCUIT HIGH





For a complete wiring diagram refer to Diagrams/Electrical.

- When Monitored:

With the ignition on and battery voltage greater than 10.4 volts.

- Set Condition:

The PCM detects that the Speed Control signal voltage is implausible.






Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test

1. DTC IS ACTIVE

NOTE: Refer to the following table when diagnosing speed control switch voltage DTCs.






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

- Go to2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking for an Intermittent DTC

2. SPEED CONTROL SWITCH





Turn the ignition off.

Remove the Speed Control Switch.

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.

Turn the ignition on.

With a scan tool, read the (V72) S/C Signal 2 voltage.

NOTE: The (V72) S/C Signal 2 voltage should be below .2 volts with the jumper wire in place.

Is the (V72) S/C Signal 2 voltage below .2 volts with the jumper wire in place?

Yes

- Replace the Speed Control Switch.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to3

3. CLOCKSPRING

Turn the ignition off.

Disconnect the Steering Control Module (SCM) C5 connector.

Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the Steering Control Module (SCM) C5 connector, not at the harness connector.

Turn the ignition on.

With a scan tool, read the (V72) S/C Signal 2 voltage.

NOTE: The (V72) S/C Signal 2 voltage should be below .2 volts with the jumper wire in place.

Is the (V72) S/C Signal 2 voltage below .2 volts with the jumper wire in place?

Yes

- Replace the Clockspring.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to4

4. STEERING CONTROL MODULE (SCM)





Turn the ignition off.

Disconnect the Steering Control Module (SCM) C2 connector.

Connect a jumper wire between the (V72) S/C Signal 2 circuit and the (V937) S/C Switch Ground circuit in the Steering Control Module (SCM) C2 harness connector.

Turn the ignition on.

With a scan tool, read the (V72) S/C Signal 2 voltage.

NOTE: The (V72) S/C Signal 2 voltage should be below .2 volts with the jumper wire in place.

Is the (V72) S/C Signal 2 voltage below .2 volts with the jumper wire in place?

Yes

- Replace the Steering Control Module (SCM).
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to5

5. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO VOLTAGE





Turn the ignition off.

Disconnect the Powertrain Control Module (PCM) connector.

Turn the ignition on.

Measure the voltage of the (V72) S/C Signal 2 circuit in the Steering Control Module (SCM) C2 harness connector.

Is there any voltage present?

Yes

- Repair the (V72) S/C Signal 2 circuit for a short to voltage.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Go to 6

6. (V72) S/C SIGNAL 2 CIRCUIT OPEN OR HIGH RESISTANCE





Measure the resistance of the (V72) S/C Signal 2 circuit between the Steering Control Module (SCM) C2 harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to7

No

- Repair the (V72) S/C Signal 2 circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

7. (V937) S/C SWITCH GROUND CIRCUIT OPEN OR HIGH RESISTANCE





Measure the resistance of the (V937) S/C Switch Ground circuit between the Steering Control Module (SCM) C2 harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

- Go to8

No

- Repair the (V937) S/C Switch Ground circuit for an open circuit or high resistance.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

8. 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

- Repair as necessary.
- Perform the PCM Verification Test Ver. 1. PCM Verification Test

No

- Replace the Powertrain Control Module (PCM).
- Perform the PCM Verification Test Ver. 1. PCM Verification Test