Cruise Control Multi-Function Input Circuit Low
The P0580 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the cruise control multi-function input circuit. This circuit carries signals from the cruise control switches (set, resume, cancel, etc.) to the PCM. A low voltage reading suggests a short to ground, a faulty switch, or a wiring issue, preventing the cruise control system from operating correctly.
1. Most Common Causes
- Faulty cruise control switch (SET/RES/ON/OFF)
- Misadjusted or defective brake or clutch pedal switch
- Erratic or missing vehicle speed sensor (VSS) signal
- Damaged cruise control actuator/servo (vacuum or electric)
- Wiring or connectors shorted to ground, shorted to power, or open circuit
- Blown fuse in the cruise control power circuit
- Internal PCM failure (rare)
2. Symptoms You Will Notice
- Cruise control inoperative
- Cruise control light on dash may flash or stay on
- Engine Check Light illuminated
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm the code and check for other related codes.
Step 2: Visually inspect the cruise control switch and wiring for damage, corrosion, or loose connections.
Step 3: Test the cruise control switch resistance with a multimeter and compare to specifications.
Step 4: Check for a short to ground in the circuit by disconnecting the switch and measuring voltage at the PCM connector.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive, but the cruise control will not function. The vehicle will operate normally otherwise.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150, depending on whether the switch or wiring needs replacement. Labor is usually minimal.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.