Throttle/Fuel Inhibit Circuit Low
The P2554 code means the vehicle's onboard diagnostic system has detected: Throttle/Fuel Inhibit Circuit Low. This is a critical severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- hard
- Estimated cost
- $150 - $800 (parts and labor)
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Common Symptoms
- Engine locked in limp mode
- No throttle response above idle
- Traction control and stability lights on
- Power steering assist may be reduced
Probable Causes (Ranked by Likelihood)
- Short to ground in inhibit circuit Very High
- Failed safety relay in inhibit system High
- Damaged inhibit circuit wiring harness Moderate
- ECM inhibit driver pulled low Low
Frequently Asked Questions
Why are my traction control and stability lights also on?
The throttle inhibit system is integrated with vehicle stability systems. When throttle is limited, the stability system also activates to maintain vehicle control.
Can I reset the limp mode?
Turning the ignition off and back on may temporarily clear limp mode, but it will re-engage once the ECM detects the fault condition again.
Is this a common failure?
P2554 is relatively uncommon and usually indicates a specific wiring fault rather than a component failure. Thorough wiring inspection is key to diagnosis.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Measure inhibit circuit voltage at ECM connector
-
Test inhibit circuit for short to ground
-
Check safety relay operation in inhibit system
-
Inspect wiring harness for physical damage
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
Commonly Affected Vehicles
- 2010-2020 Toyota Highlander
- 2012-2019 Honda Pilot
- 2008-2018 Ford Explorer
- 2011-2020 Chevrolet Traverse
Related Codes
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