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

With electronic throttle control the throttle body carries two position sensors, A and B, usually with opposite or offset signals, and the engine module compares them (correlation code P2135). GM and Ford give the pedal sensors their own codes (P2120 ff), so B is in practice the second throttle sensor. P0222 means the signal of sensor B is below its lower limit – GM about 0.25 V, Ford below 0.25 V – typically a short to ground, an open signal wire or a missing 5 V reference. Both detect it within about a second and switch the warning light on in the first trip. If the shared reference fails, several sensors report low at once. The module carries on with sensor A, limits throttle opening and power and switches off cruise control.

High severity. Can I keep driving?Be careful: the car may suddenly lose power. If it goes into limp mode, get off the highway and calmly make your way to a repair shop.

Symptoms

Check engine light and throttle warning light
Reduced power, limp mode
Poor throttle response, jerking
Cruise control disabled

Most likely causes

Signal or 5 V wire open or shorted to ground
Throttle body or sensor B faulty internally
5 V reference pulled down by another sensor
Connector corrosion or water ingress
Engine module faulty

What to check, in order

Start with the simplest. You can tick off each step.

Check the pedal and throttle connectors
With the connector unplugged, check whether the signal wire is making contact with ground.
Use live data to confirm that both sensors rise smoothly and consistently
Clean the throttle if it has carbon buildup
Run the relearn procedure with the scanner if the manufacturer requires it
Replace the part identified by the diagnosis

Good to know

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P0222 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
2: Fuel injection
22: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0222?

Be careful: the car may suddenly lose power. If it goes into limp mode, get off the highway and calmly make your way to a repair shop.

What causes code P0222?

The most common causes are: signal or 5 V wire open or shorted to ground; throttle body or sensor B faulty internally; 5 V reference pulled down by another sensor.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.