P0580

P0580-SPEED CONTROL SWITCH 1 CIRCUIT LOW





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
While the ignition is on.

- Set Condition:
Speed control MUX switch is below 1.0 Volt for five seconds.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. CHECK FOR THE S/C SWITCH VOLTAGE BELOW 1.0 VOLT
1. Turn the ignition on.
2. With the scan tool, read the S/C Switch Volts status in the PCM.

Is the S/C Switch voltage below 1.0 Volt?

Yes

- Go To 3

No

- Go To 2

2. VISUALLY INSPECT THE S/C WIRING HARNESS
1. Turn the ignition off.
2. Using the Schematics as a guide, inspect the Wiring and Connectors.

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 3

3. CHECK THE S/C SWITCH (ON/OFF)
1. Turn the ignition off.
2. Disconnect the S/C ON/OFF Switch harness connector.

NOTE: Check connectors - Clean/repair as necessary.

3. Turn the ignition on.
4. With the scan tool in Sensors, read the S/C Switch Volts in the PCM.

Did the S/C Switch Volts change to 5.0 Volts?

Yes

- Replace the S/C ON/OFF Switch.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 4

4. CHECK THE S/C SWITCH (RESUME/ACCEL)
1. Turn the ignition off.
2. Disconnect the S/C RESUME/ACCEL Switch harness connector.

NOTE: Check connectors - Clean/repair as necessary.

3. Ignition on, engine not running.
4. With the scan tool in Sensors, read the S/C Switch volts in the PCM.

Did the S/C Switch Volts go above 4.0 Volts?

Yes

- Replace the Resume/Accel Switch.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 5

5. CHECK THE CLOCKSPRING
1. Turn the ignition off.
2. Disconnect the Clockspring harness connector (instrument panel wiring side).
3. Turn the ignition on.
4. With the scan tool in Sensors, read the S/C Switch Volts in the PCM.

Did the S/C Switch Volts change to 5.0 Volts?

Yes

- Replace the Clockspring.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 6

6. CHECK THE (V37) S/C SWITCH 1 SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the S/C ON/OFF Switch harness connector.
3. Disconnect the PCM C2 harness connector.

NOTE: Check connectors - Clean/repair as necessary.

4. Measure the resistance between ground and the (V37) S/C Switch 1 Signal circuit at the S/C ON/OFF Switch harness connector.

Is the resistance below 10k Ohms?

Yes

- Repair the (V37) S/C Switch 1Signal circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 7

7. CHECK FOR THE (V37) S/C SWITCH 1 SIGNAL CIRCUIT SHORTED TO THE (V937) S/C SWITCH RETURN CIRCUIT




1. Measure the resistance between the (V37) S/C Switch Signal circuit and the (V937) S/C Switch Return circuit at the ON/OFF switch harness connector.

Is the resistance below 10k Ohms?

Yes

- Repair the short between the (V37) S/C Switch 1 Signal circuit and the (V937) S/C Switch Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.