P0220 Code: Throttle/Pedal Position Sensor/Switch B Circuit

What the P0220 code means

Electronic throttles carry two or three position tracks for safety. Depending on the manufacturer, track B belongs to the throttle body (the throttle plate) or to the accelerator pedal. The computer compares all the tracks against each other, and if they do not agree, it limits power.

The P0220 code is stored when the computer detects a general electrical fault in the circuit. The sensor works with a 5 V reference, a ground and a signal that should vary between about 0.5 and 4.5 V. The extreme values (close to 0 V or close to 5 V) are reserved for detecting faults: a signal that sits at them does not match any real position or pressure.

For as long as the fault is there, the computer stops trusting that track and works only from the other one. For safety, it limits throttle opening and pedal response: the vehicle moves but with very little power, and the idle can end up a bit high. It is the behavior many drivers describe as the car will not accelerate.

Remember that the code tells you where the computer saw the problem, not which part is broken. Look up how the throttle position sensor is tested if you need the step-by-step procedure.

P0220 code symptoms

• Check engine light on (sometimes the power control light too).
• Limp mode with limited power.
• Slow or no response from the accelerator.
• Other related codes for the same sensor.

Likely causes of the P0220 code

1. Connector damaged or loose. The most common cause.
2. Wiring cut or shorted between the sensor and the computer.
3. Failed sensor, open or shorted.
4. 5 V reference missing. Check whether other sensors are failing too.
5. Computer. Uncommon; rule out everything above first.

How to diagnose the P0220 code step by step

1. Read the signals on the scan tool and compare them with the other tracks or with the desired pressure.
2. Inspect the connector: look for green, backed-out or oily pins and check that the lock is closed.
3. Check 5 V and ground at the connector with the key on: 4.8 to 5.1 V on the reference and less than 0.1 V of drop on the ground.
4. Measure the signal with the connector plugged in while you move the pedal or the throttle, or accelerate (turbo): it should change smoothly, with no jumps or drops to zero.
5. Do the harness wiggle test with the engine running: move the wiring and watch the reading.
6. Check the continuity of each wire to the computer with the key off (less than 1 ohm).
7. Compare tracks A and B on the scan tool with the pedal at rest and then pressed slowly: they should move together, each within its own range.
8. After repairing, run the relearn of the throttle and pedal position following the manufacturer procedure.

How to fix the P0220 code

• Repair the connector or the wiring.
• Replace the sensor (on electronic throttles, normally the pedal or the whole throttle body).
• Run the throttle relearn if the manufacturer calls for it.
• Clear the codes and verify on the road.

Technical reference data

• 5 V reference, ground and a signal of roughly 0.5 to 4.5 V.
• Tracks A and B: they usually have different slopes or run in opposite directions.
• Approximate values only: check the manufacturer data for your engine.

Brand-specific notes

Track naming varies from one manufacturer to another.

P0220 on GM

The pedal tracks are often identified as D, E and F.

P0220 on Chrysler

The pedal tracks are often identified as D, E and F.

P0220 on Ford

The throttle body and the pedal have two tracks each.

P0220 on Toyota

The throttle body and the pedal have two tracks each.

P0220 on Volkswagen

The throttle body and the pedal have two tracks each.

Frequently asked questions about P0220