P0576

What it means

P0576 is the generic code for a low voltage fault in the cruise control input circuit. The engine or powertrain control unit has seen the signal from the cruise control switch or command circuit drop below the expected range, usually a short to earth or an open circuit. The cruise control function is normally disabled while the fault is present.

Symptoms

• Cruise control will not engage or set a speed
• Cruise control cuts out unexpectedly
• Cruise control indicator light not working or flashing
• Malfunction indicator lamp may be on
• Steering wheel or stalk cruise buttons seem dead or intermittent

Possible causes

• Faulty cruise control switch or steering wheel/stalk control assemblylikely
• Damaged wiring, such as chafing or a short to earth in the cruise control input circuitlikely
• Corroded, loose or contaminated connector at the switch, clock spring or control unitpossible
• Worn or damaged clock spring (spiral cable) in the steering column, on vehicles that use onepossible
• Brake or clutch pedal switch fault affecting the cruise control circuit, depending on modelpossible
• Faulty control unit input circuit or software issuerare

How to diagnose

1. Read all stored codes and freeze frame data, and note whether other cruise, brake switch or steering column codes are present
2. Check the cruise control buttons and stalk for physical damage, sticking or spilled liquid
3. Inspect the wiring and connectors between the switch and the control unit for chafing, corrosion, water ingress and poor pin tension
4. Using live data, watch the cruise switch input while pressing each button and see whether the reading responds correctly
5. Check the brake and clutch pedal switches operate correctly and that their signals are plausible in live data, as applicable to the model
6. With the battery disconnected and the wiring diagram for the vehicle to hand, test the input circuit for a short to earth and for resistance, and check the switch resistance in each position
7. Check the clock spring continuity where fitted, following the manufacturer procedure and taking airbag safety precautions
8. Clear the code and road test to confirm that it does not return

How to fix

• Replace the faulty cruise control switch or stalk assembly
• Repair or replace damaged wiring to remove the short to earth or open circuit
• Clean, repair or replace corroded or loose connectors
• Replace the clock spring if it is found faulty, following the airbag safety procedure
• Replace a faulty brake or clutch pedal switch if it is the cause
• Repair or replace the control unit, or update its software if the manufacturer lists it as a known fix, only after the wiring and switches are proven good

Can I keep driving?

Nearby codes

• P0575GenericCruise Control Input Circuit
• P0577GenericCruise Control Input Circuit High