P0222: Throttle/Pedal Position Sensor/Switch "B" Circuit Low

What does P0222 mean?

The sensor sends a voltage that changes with throttle or pedal position. P0222 is a circuit low code: the B signal voltage is below what the sensor should produce at any position.

On cars with electronic throttle control, the computer compares two or more position signals for safety. When one signal is out of range, many cars limit power (often called limp mode) until the fault is fixed.

Common symptoms

• Check engine light on
• Poor acceleration or loss of power
• Hard starting in some cases
• Accelerator pedal may feel unresponsive

Common causes

The causes below are the ones commonly seen with P0222. The actual cause can vary by vehicle, engine and mileage, so treat this list as a starting point, not a diagnosis.

• A faulty throttle or pedal position sensor
• Unplugged, damaged or corroded wiring or connectors in the sensor circuit

What to check with a scanner

• With the key on and engine off, watch throttle and pedal position values in Live data while slowly pressing the pedal.
• Inspect the connector at the throttle body and at the accelerator pedal.
• Read freeze frame data and note any related codes such as P0221, P0223 or P2135.
• Clear the code and see whether it returns at once or only when the harness moves.

How to read and clear P0222 with OBD Master Pro

1. Plug in your adapter. Connect a generic ELM327 (or ELM329) OBD2 adapter to the diagnostic port, usually under the dashboard on the driver's side. Bluetooth Classic, Bluetooth LE, Wi-Fi and USB OTG adapters are supported.
2. Switch the ignition on. Turn the key to ON or start the engine, depending on your car.
3. Connect in OBD Master Pro. Open the app, go to Connection and pick your adapter. Classic Bluetooth adapters connect from the Bluetooth tab, Bluetooth LE adapters from the BLE tab with no pairing needed. Use the generic OBD2 / EOBD profile or your car's brand profile.
4. Read the codes. Open the fault codes screen to see stored, pending and permanent codes. Confirm P0222 is listed and note any other codes, since they often explain the cause.
5. Check the details. Look at freeze frame data, Live data and, where your car supports it, Mode 06 test results (see the checks above).
6. Fix, then clear. After the repair, clear the codes to turn off the check engine light. Clearing also resets the emissions readiness monitors, so drive normally and check the readiness screen before any inspection. Permanent codes cannot be erased with a scan tool; they clear on their own once the car's self test passes.

Tip: you can also look up P0222 and other codes in the app's DTC search without connecting to a car. If your adapter will not connect, use Connection > Share connection log and email it to support. Many cheap ELM327 clones only handle basic engine OBD2, which is all you need for P0222.

When to see a mechanic

Get professional help if any of these apply:

• The car enters reduced power mode
• The accelerator does not respond normally
• Wiring needs to be tested with a meter

If you are unsure, a qualified technician can confirm the cause with tests such as smoke testing, pressure testing or scope readings. Clearing a code does not repair the fault.

Related trouble codes

See all OBD2 trouble code guides

Related guides

Check engine light on: what to do · How to read an OBD2 code (P, B, C, U) · Stored, pending and permanent codes and freeze frame · OBD2 readiness monitors explained · OBD2 glossary · OBD2 by car brand