P2135 — Throttle/Pedal Position Sensor A/B Voltage Correlation
Moderate severityWhat it means
P2135 is stored when the engine control unit sees a fault involving the throttle/pedal position sensor A/B correlation. The control unit compares the two main throttle/pedal position signals (A and B) for safety; this code means the two no longer agree.
Common symptoms
- Reduced power or limp mode (very common)
- Hesitation or poor throttle response
- Unstable idle
Likely causes
- A worn throttle body or pedal sensor
- A connector or wiring fault on one of the two circuits
What to check first
- Compare the A and B signals in live data — they should move together
- Inspect both connectors and the throttle body wiring
Can you keep driving?
This very often triggers reduced power; have it checked promptly as throttle response can be unpredictable.
Frequently asked questions
What is the most common cause of P2135?
The most likely cause is: A worn throttle body or pedal sensor. Several other faults can set P2135 as well, so confirm the real cause with live data and the checks above before replacing any parts.
Can I just clear P2135 and keep driving?
Clearing P2135 with an OBD2 scanner turns the warning light off, but if the underlying fault has not been repaired the code will usually come back within a few drive cycles. Fix the cause first, then clear the code to confirm the repair worked.
How serious is P2135?
P2135 is a moderate-severity code. The car is often still drivable, but have it diagnosed soon — the underlying problem can get worse and it may fail an emissions test.
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