What are the common causes of P2555?

Short to power in the throttle/fuel inhibit A circuit. Failed throttle position sensor holding voltage high. Vacuum leak skewing throttle input. Faulty ECM inhibit driver.

Read throttle/fuel inhibit A circuit voltage on a scan tool. Check the inhibit A signal wire for a short to power. Test the throttle position sensor output range. Smoke-test the intake for vacuum leaks. Replace the throttle position sensor if it reads high. Clear the code and retest.

P2555

Throttle/Fuel Inhibit A Circuit High

System: Speed and idle control (P code)
Lamp: Check Engine Light
Category: Powertrain - Computer and Auxiliary Controls

What it means

P2555 means Throttle/Fuel Inhibit A Circuit High.

Check these first

Short to power in the throttle/fuel inhibit A circuit
Failed throttle position sensor holding voltage high
Vacuum leak skewing throttle input
Faulty ECM inhibit driver

What to do next

Read throttle/fuel inhibit A circuit voltage on a scan tool
Check the inhibit A signal wire for a short to power
Test the throttle position sensor output range
Smoke-test the intake for vacuum leaks
Replace the throttle position sensor if it reads high
Clear the code and retest

Look up another code

Code or symptom

Enter a full code or a symptom. Press / to search. How to read a code

Type a code above, or start from a symptom or a common code.

Updated

Generic SAE J2012 definition. Last updated 2026-10-10.