P2552
Throttle/Fuel Inhibit A Circuit
General electrical fault on the throttle/fuel inhibit input A. This input lets external safety functions (immobilizer, hybrid HV interlock, anti-theft) override the throttle or cut fuel delivery. With the input invalid the safety override is unreliable, so the ECM falls back to its safe default — typically inhibit asserted to err on the side of safety.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Open or shorted inhibit wireCommon
Parts involved
- Throttle Inhibit A
P2552 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.