Throttle/Fuel Inhibit Circuit High Voltage
The P2555 code indicates that the powertrain control module (PCM) has detected a high voltage condition in the throttle/fuel inhibit circuit. This circuit is responsible for controlling fuel delivery and throttle operation under certain conditions, such as during a collision or when the vehicle is in a reduced power mode. A high voltage reading suggests a short to power, a faulty sensor, or a wiring issue, which can lead to improper fuel management and throttle response.
1. Most Common Causes
- Short circuit to battery voltage (B+) in the inhibit circuit wiring
- Throttle/fuel inhibit switch or sensor internally shorted or damaged
- Open or high-resistance reference ground circuit
- Corroded, oxidized, or bent pins/connectors in the affected circuit
- Internal PCM failure in the signal detection channel
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or limp mode
- Engine stalling or hesitation
- Poor fuel economy
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the throttle/fuel inhibit circuit wiring and connectors for damage, corrosion, or shorts.
Step 3: Use a multimeter to check for high voltage (above 5V) at the circuit while the ignition is on.
Step 4: Test the throttle/fuel inhibit relay and solenoid per manufacturer specifications.
Step 5: If all else is normal, check for PCM issues or perform a PCM reset.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can cause sudden loss of power or stalling, which may lead to an accident. Have the vehicle diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on the root cause. If a relay or wiring repair is needed, it may be on the lower end; if the PCM needs replacement, costs can exceed $500.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.