P0221

Throttle/Pedal Position Sensor/Switch B Circuit Range/Performance

Car Fault Codes Fuel & air

Can you still drive? With care, short trips only

Who can fix it? Needs a workshop

Typical repair time 30 minutes – 2 hours

Typical cost SAR 100 to 2,500

What it means

This code means the B signal from the throttle position sensor or accelerator pedal sensor is present but does not agree with the other signal or with the expected value. The computer treats the signal as unreliable and usually limits engine power for safety.

Symptoms4

Check engine light on with reduced power or limp mode.
Jerky acceleration or acceleration that does not match pedal input.
Unstable idle.
The fault may appear only at a certain pedal position.

Possible causes5

Worn internal sensor track at a certain point, so the reading jumps or drifts.
Extra resistance in the connector or wiring from corrosion or moisture.
Heavy dirt or sticking in the throttle body so its position does not match the command.
Failed electronic throttle body assembly or pedal sensor.
Incorrect replacement part or a skipped relearn procedure after replacement.

How to diagnose5

Watch both sensor signals together on a scan tool through the full range of travel and confirm they change smoothly and in the correct relationship.
Graph the signal with an oscilloscope to catch any momentary dropout at a certain position.
Inspect the connector and wiring for corrosion or extra resistance, and measure the voltage drop on the ground circuit.
Visually check the throttle body for dirt and free movement, with the battery disconnected or as the manufacturer directs.
Confirm the throttle relearn was done if the part or battery was recently replaced.

How to fix5

Clean the connector and repair wiring with extra resistance.
Clean a dirty throttle body with a dedicated cleaner, then perform the relearn.
Replace the pedal sensor if its signal is not smooth.
Replace the throttle body assembly if its built-in sensor is proven worn.
Clear the codes, then road test and confirm the code does not return.

Repair cost

0–500

500–2,000

2,000–5,000

5,000+

In Saudi riyals; the highlighted part is the expected range for this fault.

A throttle cleaning or connector repair may be enough at low cost; the cost rises for a pedal sensor and reaches the upper end for an electronic throttle body assembly.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026

Frequently asked questions

What is the difference between P0221, P0222 and P0223?

P0222 and P0223 mean the voltage is below or above its limits, while P0221 means the signal is within electrical limits but does not behave logically or does not match the other signal.

Why does the fault appear at one pedal position?

Because sensors usually wear at the most-used positions, so the signal drops out briefly only at that spot.

Can I drive with this code?

Only a short distance and with care, because the computer may cut power suddenly while driving.

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This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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