P2555 — Throttle control electrical circuit voltage too high

The engine control module detected an unusually high voltage in the throttle or fuel inhibit circuit. This usually means a wiring problem, a faulty throttle body, or an issue with the electronic control unit. It prevents the engine from responding correctly to throttle input, which can affect drivability and safety.

Common causes

The cause is almost always one of a few things. Here they are — P2555 rarely comes from anything outside this list:

• Damaged or corroded wiring in throttle circuit
• Faulty throttle position sensor or throttle body
• Malfunctioning engine control unit (ECU)
• Poor electrical connections or grounding issues

Where to start

In the order a sensible mechanic would work — the cheap checks first, the expensive replacements only after:

1. Inspect and repair wiring and connectors in throttle circuit
2. Clean and test throttle body and sensor function
3. Check ECU for faults and update or reprogram if needed
4. Replace throttle body assembly if necessary

That is what holds for P2555 in general. From here it depends on your engine — tell me which car it is and what it does, and I will give you the steps for it: real procedures, torque figures and diagrams instead of general advice.