Accelerator Pedal Position Sensor 1
The accelerator pedal position sensor is reading a fault.
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 pedal position sensor tells the engine how far you push the gas pedal—if it fails, the engine doesn't know how much power to give you.
What the computer is actually seeing
The computer monitors two signals from the accelerator pedal position sensor: 0.5V at rest and up to 4.5V at full throttle. If it detects voltages outside of this range or if the signals are inconsistent, it triggers the fault code.
What a healthy reading looks like
Expected voltage should range from 0.5V (idle) to 4.5V (full throttle) when tested at the sensor output under normal operation.
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. Start by visual inspecting the wiring and connectors for damage or corrosion. Check that all connections are secure. If anything looks bad, repair or replace before going further. Decision: If wiring/connectors are good, proceed to Step 2. If damaged, repair and retest.
- 22. With the key on, engine off, backprobe the sensor connector. Measure output voltage at idle—it should be around 0.5V. Decision: If output is normal, proceed to Step 3. If not, replace the sensor.
- 33. While monitoring the voltage, slowly push the accelerator pedal to the floor. At full throttle, the voltage should reach approximately 4.5V. Decision: If voltage ranges correctly from 0.5V to 4.5V, the pedal is likely fine. If not, replace the sensor.
Common causes
- Wiring issues such as shorts or open circuits
- Faulty accelerator pedal position sensor
- Bad connector or corrosion
- ECU issues causing false readings
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but expect reduced performance, and avoid heavy acceleration. You may experience a limited throttle response.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, it will likely return after a drive cycle.
Why does this code sometimes pair with SPN 975?
SPN 975 indicates a possible issue with a second sensor; faults in these systems often occur together due to shared wiring or common component failures.
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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