P0580 LOW VOLTAGE DETECTED AT THE SPEED CONTROL SWITCH
When Monitored and Set Condition:
When Monitored: While the ignition is on
Set Condition: Speed control MUX switch below 1.0 volts for 5 seconds.
POSSIBLE CAUSES
- S/C WIRING HARNESS OBSERVABLE PROBLEM
- S/C SWITCH (ON/OFF)
- CLOCKSPRING SHORTED TO GROUND
- S/C SWITCH (RESUME/ACCEL)
- S/C SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
- S/C SIGNAL CIRCUIT SHORTED TO SENSOR GROUND
- ECM
DIAGNOSTIC PROCEDURE
-
Turn the ignition on. With the DRBIII®, read the S/C Switch volts status in the ECM. Is the S/C Switch voltage below 1.0 volt?
Yes --> Go To 3
No --> Go To 2 -
Turn the ignition off. Using the Schematics as a guide, inspect the Wiring and Connectors. Were any problems found?
Yes --> Repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Go To 3 -
Turn the ignition off. Disconnect the S/C ON/OFF Switch harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Turn the ignition on. With the DRBIII® in Sensors, read the S/C Switch volts in the ECM. Did the S/C Switch volts change to 5.0 volts?
Yes --> Replace the S/C ON/OFF Switch. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Go To 4 -
Turn the ignition off. Disconnect the S/C RESUME/ACCEL Switch harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Ignition on, engine not running. With the DRBIII® in Sensors, read the S/C Switch volts in the ECM. Did the S/C Switch volts go above 4.0 volts?
Yes --> Replace the Resume/Accel Switch. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Go To 5 -
Turn the ignition off. Disconnect the clockspring 6-way harness connector (instrument panel wiring side). Turn the ignition on. With the DRBIII® in Sensors, read the S/C Switch volts in the ECM. Did the S/C Switch volts change to 5.0 volts?
Yes --> Replace the Clockspring. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Go To 6 -
Turn the ignition off. Disconnect the S/C ON/OFF Switch harness connector. Disconnect the ECM harness connectors.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the S/C Switch Signal circuit and ground (B-) at S/C ON/OFF Switch harness connector. Is the resistance below 5.0 ohms?
Yes --> Repair S/C Switch Signal Circuit for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Go To 7 -
Measure the resistance between the S/C Signal Circuit and the Sensor Ground Circuit at the ON/OFF switch harness connector. Is the resistance below 5.0 ohms?
Yes --> Repair S/C Signal Circuit shorted to Sensor Ground. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).
No --> Replace and program the ECM in accordance with the Service Information. Perform POWERTRAIN VERIFICATION TEST VER - 4 (DIESEL).