P0580

P0580-SPEED CONTROL SWITCH 1 CIRCUIT LOW

For a complete wiring diagram REFER to DIAGRAMS/ELECTRICAL

- When Monitored:
With the engine running and battery voltage greater than 10 volts.

- Set Condition:
The PCM detects that the sensor input voltage is below the minimum acceptable value.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE
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 SIGNAL 1 VOLTAGE
WARNING: Disconnect and isolate the battery negative (ground) cable before beginning steering wheel removal or installation. Allow the front airbag system capacitor to discharge for two minutes before removing the steering wheel or any front airbag system component. This will disable the front airbag system. Failure to disconnect the battery could result in accidental front airbag module deployment and possible personal injury.Do not place a non-deployed airbag face down on a hard surface as the airbag will propel into the air if accidentally deployed, and could result in serious or fatal injury.

Turn the ignition off.
Remove the Speed Control Switch.
Turn the ignition on.
With a scan tool, read the (V37) S/C Signal 1 voltage.

NOTE: The Speed Control Signal 1 voltage should be above 4.8 volts with the Speed Control Switch connector disconnected.

Is the Speed Control Signal 1 voltage above 4.8 volts with the Speed Control Switch connector disconnected?

Yes

- Go to7

No

- Go to3

3. (V37) S/C SIGNAL 1 CIRCUIT SHORTED TO GROUND

Turn the ignition off.
Disconnect the Powertrain Control Module (PCM) connector.
Measure the resistance between ground and the (V37) S/C Signal 1 circuit in the Speed Control Switch harness connector.
Is the resistance above 100 ohms?

Yes

- Go to 4

No

- Repair the (V37) S/C Signal 1 circuit for a short to ground.
- Perform the PCM Verification Test.Powertrain Verification Test

4. (V37) S/C SIGNAL 1 CIRCUIT SHORTED TO THE (V937) S/C SWITCH GROUND CIRCUIT

Measure the resistance between the (V37) S/C Signal 1 circuit and the (V937) S/C Switch Ground circuit in the Speed Control Switch harness connector.
Is the resistance above 100 ohms?

Yes

- Go to 5

No

- Repair the (V37) S/C Signal 1 circuit for a short to the (V937) S/C Switch Ground circuit.
- Perform the PCM Verification Test.Powertrain Verification Test

5. (V37) S/C SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE

NOTE: 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 (V937) S/C Switch Ground circuit between the Speed Control Switch harness connector and the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

Yes

- Go to7

No

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

7. SPEED CONTROL SWITCH
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 related connectors.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Replace the Speed Control Switch.
- Perform the PCM Verification Test.Powertrain 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. Verify that there is good pin to terminal contact in the related connectors.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test.Powertrain Verification Test

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test.Powertrain Verification Test