P0592

P0592-SPEED CONTROL SWITCH 2 CIRCUIT LOW





For a complete wiring diagram Consult 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. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. ACTIVE DTC
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 DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition.

2. SPEED CONTROL ON/OFF SWITCH
With the scan tool, monitor the Speed Control Switch voltage.
Disconnect the Speed Control On/Off Switch harness connector.
Did the voltage change to above 4.7 volts?

Yes

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

No

- Go To 3

3. SPEED CONTROL RESUME/ACCEL SWITCH
With the scan tool, monitor the Speed Control Switch voltage.
Disconnect the Speed Control Resume/Accel Switch harness connector.
Did the voltage change to above 4.7 volts?

Yes

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

No

- Go To 4

4. STEERING COLUMN CONTROL MODULE
Turn the ignition off.
Disconnect the C1 Steering Column Control Module harness connector (instrument panel wiring side).
Ignition on, engine not running.
With the scan tool, read the S/C Switch voltage.
Did the S/C Switch volts change to 5.0 volts?

Yes

- Replace the Steering Column Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 5

5. (V372) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Connect the C3 Steering Column Control Module harness connectors.
Disconnect the C3 PCM harness connector.
Measure the resistance between ground and the (V372) S/C Switch No.2 Signal circuit in the S/C Switch harness connectors.
Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (V372) S/C Switch No.2 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 6

6. (V72) S/C SWITCH SENSE 2 CIRCUIT SHORTED TO GROUND




Measure the resistance between ground and the (V72) S/C Switch Sense 2 circuit in the C1 SCCM harness connector.
Is the resistance below 100 ohms?

Yes

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

No

- Go To 7

7. (V372) S/C SWITCH NO.2 SIGNAL CIRCUIT SHORTED TO THE (V397) S/C SWITCH RETURN CIRCUIT




Measure the resistance between the (V397) S/C Switch Return circuit and the (V372) S/C Switch No.2 Signal circuit in the S/C Switch harness connectors.
Is the resistance below 5.0 ohms?

Yes

- Repair the short between the (V372) S/C Switch No.2 Signal circuit and the (V397) S/C Switch Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 8

8. (V72) S/C SWITCH SENSE 2 CIRCUIT SHORTED TO THE (V937) S/C SWITCH RETURN CIRCUIT




Measure the resistance between the (V72) S/C Switch Sense 2 circuit and the (V937) S/C Switch Return circuit in the C1 SCCM harness connector.
Is the resistance below 5.0 ohms?

Yes

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

No

- Go To 9

9. SPEED CONTROL SWITCH VOLTAGE VALUES
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 and #8815-1 to perform diagnosis.

Install Miller Special Tool #8815-1 on the C3 PCM harness connector.
Connect the S/C Switch harness connectors.
Connect the SCCM harness connectors.
Turn the ignition on.
With a scan tool, monitor the S/C Switch voltage readings.
Using a voltmeter check the voltage on the (V37) S/C Switch Sense 1 circuit and the (V38) S/C Switch Sense 2 circuit at the appropriate terminals of the special tool #8815.
Monitor the voltmeter.
With a scan tool, monitor the S/C Switch voltage readings.





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 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. Verify that there is good pin to terminal contact in the Switch and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
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.