Throttle Position Sensor Fault
Indicates a problem with the throttle position sensor signal.
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 throttle position sensor tells the engine control module how open the throttle is, affecting the engine's power and efficiency. If it fails, the engine may not respond properly to the accelerator.
What the computer is actually seeing
The engine control module expects the throttle position to vary between 0 and 100% as the accelerator pedal is pressed. If it detects that the position data stays constant or is outside these ranges, it flags the fault.
What a healthy reading looks like
Throttle position readings between 0% (closed) and 100% (fully open). Voltage should range from 0.5V to 4.5V as the throttle plate opens.
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 the throttle position sensor wiring and connector for damage or corrosion. Repair as necessary. Decision: If damaged, fix the issue; if not, proceed to next step.
- 22. Measure the throttle position sensor voltage with a multimeter while moving the throttle plate. Expected readings should vary between 0.5V and 4.5V. Decision: If readings are out of range, replace the sensor; if within range, proceed to next step.
- 33. Inspect the ECM for stored trouble codes related to throttle input. Clear codes and retest. Decision: If SPN 8105 reappears, the ECM may be faulty; consider reprogramming or replacing the ECM.
Common causes
- Faulty throttle position sensor
- Wiring or connector issues
- Electrical short or open in the throttle circuit
- Faulty ECM software
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
Yes, but drivability may be affected, and engine performance could diminish.
Will this code come back after clearing it?
If the underlying issue is not resolved, yes, it will likely return.
Why does this code appear with other sensor codes?
A malfunctioning throttle position sensor can affect other systems or indicate broader wiring issues.
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