Accelerator Pedal Position Sensor 1
The accelerator pedal position sensor 1 circuit is out of range.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The accelerator pedal position sensor measures how far down you press the gas pedal; if this reading is too high or too low, it can signal issues with your throttle control.
What the computer is actually seeing
The Engine Control Module (ECM) expects the accelerator pedal position to fall within a specific voltage range—typically 0.5V to 4.5V. If it goes outside these limits, it triggers the fault code.
What a healthy reading looks like
Expected values are 0.5V at closed position and around 4.5V at fully pressed position.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check for any visible damage to the wiring and connectors related to the accelerator pedal position sensor.
- 2Verify the accelerator pedal moves freely without binding or obstruction. Use a multimeter to measure the voltage output of the sensor while moving the pedal; it should vary smoothly from 0.5V to 4.5V.
- 3Inspect the ECM for any fault codes indicating sensor failures, or check for software/firmware updates that may resolve known issues.
Common causes
- Faulty accelerator pedal position sensor
- Wiring issues or poor connections
- ECM malfunction
- Mechanical binding in the throttle linkages
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, driving with SPN 225 can lead to loss of throttle response, making it potentially dangerous.
Will the fault return after clearing?
Yes, if the underlying issue is not resolved, the code will likely return.
Why does it sometimes pair with other codes?
Shifts in accelerator position can trigger multiple sensor-related codes; they often indicate interconnected issues.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →