Cruise Control Input Circuit Low
The P0576 code indicates that the Powertrain Control Module (PCM) has detected a low voltage signal from the cruise control input circuit. This typically occurs when the brake switch, clutch switch (manual transmission), or the cruise control switch itself is malfunctioning, or there is a wiring issue such as a short to ground or open circuit. The PCM monitors the voltage on this circuit to determine when the driver cancels or disengages cruise control; a low voltage reading suggests the circuit is stuck in a closed or grounded state.
1. Most Common Causes
- Faulty brake switch (stuck closed or shorted)
- Faulty clutch switch (manual transmission)
- Short to ground in cruise control wiring
- Open circuit in cruise control input circuit
- Faulty cruise control switch or module
2. Symptoms You Will Notice
- Cruise control inoperative
- Cruise control light on dash stays on or off
- Brake lights may not work properly
- Vehicle may not start if clutch switch is faulty (manual)
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify the code and check for other related codes.
Step 2: Inspect the brake switch for proper operation and adjustment; test for voltage and continuity.
Step 3: Check the clutch switch (if manual) for proper operation.
Step 4: Visually inspect wiring and connectors for damage, corrosion, or shorts.
Step 5: Test the cruise control switch and module per manufacturer specifications.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, the vehicle is generally safe to drive, but cruise control will not work. If the brake lights are affected, it may reduce safety.
How much does it cost to fix?▼
Typically $50 to $150 for diagnosis and repair, depending on the cause. A brake switch replacement is often around $50-$100.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.