P0592

P0592-SPEED CONTROL SWITCH 2 CIRCUIT LOW





For a complete wiring diagram refer to Diagrams/Electrical.


- When Monitored:

With the ignition key on.

- Set Condition:

Speed control switch input No.2 is below the minimum acceptable voltage at the PCM. One trip fault.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.


Diagnostic Test


1. ACTIVE DTC

NOTE: Do not press any of the Speed Control Switch buttons.

Start the engine.

Allow the engine 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 can result in personal injury or death.

With a scan tool, select View DTCs.


NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.

Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition

m SPEED CONTROL SWITCH

With the scan tool, monitor the Speed Control Switch voltage.

Disconnect the Speed Control Switch harness connector.

Did the voltage change to above 4.7 volts?

Yes

- Replace the Speed Control Switch.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 3


3. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO GROUND





Turn the ignition off.

Disconnect the C3 PCM harness connector.

Measure the resistance between ground and the (V72) S/C Signal 2 circuit in the Switch harness connector.

Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (V72) S/C Signal 2 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 4


4. (V72) S/C SIGNAL 2 CIRCUIT SHORTED TO THE (V937) S/C RETURN CIRCUIT





Measure the resistance between the (V72) S/C Signal 2 circuit and the (V937) S/C Return circuit in the Switch harness connector.

Is the resistance below 5.0 ohms?

Yes

- Repair the short between the (V72) S/C Signal 2 circuit and the (V937) S/C Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 5


5. (V72) S/C SIGNAL 2 CIRCUIT OPEN





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 Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (V72) S/C Signal 2 circuit from the Switch harness connector to the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes

- Go To 6

No

- Repair the excessive resistance in the (V72) S/C Signal 2 circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test


6. SPEED CONTROL SWITCH VOLTAGE VALUES

Allow the engine to idle.

With a scan tool, monitor the S/C Switch voltage readings.







Take these same voltage measurements with a voltmeter by back probing the (V72) S/C Signal 2 circuit at the switches.

Compare the voltage readings on the voltmeter to what the scan tool displayed.

Are the voltage readings out of the listed specification and is there less than a 0.2 of a volt difference between the voltmeter switch values and the scan tool switch values?

Yes

- Replace the Speed Control Switch.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 7


7. PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test