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P0580

P0580-SPEED CONTROL SWITCH 1 CIRCUIT LOW

P0580 - Speed Control Switch 1 Circuit Low:






WHEN MONITORED
With the ignition key on. Battery voltage above 10 volts.

SET CONDITION
When switch voltage is less than 0.43 of a volt for 18.4 seconds. One trip fault. Three good trips to turn off the MIL.

POSSIBLE CAUSES
- (V37) S/C signal no.1 circuit shorted to ground
- (V37) S/C signal no.1 circuit shorted to the (K900) sensor ground circuit
- Clockspring
- Speed control on/off switch
- Speed control resume/accel switch
- PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

DIAGNOSTIC TEST

1. SPEED CONTROL SWITCH VOLTAGE LOW

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

Ignition on, engine not running.
With a scan tool, read the Speed Control voltage.

Q: Is the Speed Control voltage below 1.0 volt?

YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Component Tests and General Diagnostics
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. SPEED CONTROL ON/OFF SWITCH
Ignition on, engine not running.
With the scan tool, monitor the Speed Control Switch voltage.
Disconnect the Speed Control On/Off Switch harness connector.

Q: 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.

Q: 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. CLOCKSPRING
Turn the ignition off.
Disconnect the clockspring 6-way harness connector (instrument panel wiring side).
Ignition on, engine not running.
With the scan tool, read the S/C Switch voltage.

Q: Did the S/C Switch volts change to 5.0 volts?

YES: Replace the Clockspring.
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 5

5. (V37) S/C NO.1 SIGNAL CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Disconnect the C3 PCM harness connector.
Measure the resistance between ground and the (V37) S/C Signal circuit in the Switch harness connector.

Q: Is the resistance below 100 ohms?

YES: Repair the short to ground in the (V37) S/C Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 6

6. (V37) S/C SIGNAL NO.1 CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT




Measure the resistance between the (K900) Sensor ground circuit and the (V37) S/C Signal No.1 circuit in the Speed Control Switch.

Q: Is the resistance below 5.0 ohms?

YES: Repair the short between the (V37) S/C Signal No.1 circuit and the (K900) Sensor ground circuit.
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.

Q: 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