Accelerator Pedal Position Sensor 1 Circuit Range/Performance Problem
There’s a performance issue with the accelerator pedal position sensor.
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 tracks the angle of the pedal to tell the engine how much power to deliver. When it sends back an incorrect reading, the engine control unit (ECU) doesn't know how much fuel to inject, causing performance issues.
What the computer is actually seeing
The ECU expects the accelerator pedal position sensor to send a voltage signal that varies from 0.5V (pedal fully released) to about 4.5V (pedal fully depressed). If it sees readings outside this range or inconsistent data, it sets a fault code.
What a healthy reading looks like
0.5V to 4.5V depending on pedal position; normal operation shows voltage increase as the pedal is pressed.
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.
- 11. Check for obvious wiring issues around the accelerator pedal and sensor. Look for fraying, disconnections, or corrosion. If found, repair or replace as needed. Decision: is the wiring good? Yes: go to step 2; No: repair wiring and retest.
- 22. Use a multimeter to measure the voltage output of the accelerator pedal position sensor while operating the pedal. Check if the readings range from 0.5V to 4.5V smoothly. Decision: is the voltage smooth and within range? Yes: go to step 3; No: replace the sensor.
- 33. Verify the ECU sensors and software by scanning for other fault codes. Check if any related codes are present. Decision: are there related codes? Yes: address them; No: the issue may be with the ECU itself, consider a software update.
Common causes
- Faulty accelerator pedal position sensor
- Wiring or connector issues
- Corrosion or damage in the pedal assembly
- Software issues in the ECU
- Other related sensor failures
Typical repair cost
$$$
Related codes
Frequently asked questions
Can I drive with this code?
You can drive, but performance will be affected. It's best to fix it soon to avoid worsening issues.
Will this code come back after the fix?
If the underlying issue is resolved, it should not come back. If it does, further diagnostics are needed.
Why does this code pair with SPN 429?
SPN 429 is often triggered by similar issues with the accelerator pedal or throttle position sensors.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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