P0220
Throttle/Pedal Position Sensor/Switch B Circuit Malfunction
Encountering the engine check light code P0220 signifies an explicit mechanical or electrical operational breakdown categorized as "Throttle/Pedal Position Sensor/Switch B Circuit Malfunction". Professional scanner tools usually flag this subsystem loop early on.
Driver's Summary
Your vehicle's computer logged P0220 after detecting a malfunction in the throttle/pedal position sensor/switch b circuit malfunction system. On the road, this usually shows up as limp mode activated, no throttle response. This condition is classified as high severity. Prompt diagnosis is essential to prevent cascading damage to related components.
Symptoms
Limp mode activated, no throttle response
Common Causes
- Defective accelerator pedal position sensor
- Faulty throttle body
- Damaged wiring near the pedal
- Corroded connector
How to Fix
- 1 Replace accelerator pedal assembly
- 2 Replace electronic throttle body
- 3 Repair pedal wiring
- 4 Clean connector contacts
Technical Explanation
The PCM triggers P0220 after its internal monitoring routine detects that a specific circuit or sensor has exceeded its acceptable operating range. The PCM monitors crankshaft rotational velocity via the CKP sensor at a resolution of individual tooth gaps on the reluctor ring. A combustion event in each cylinder produces a measurable acceleration spike; its absence or weakness is flagged as a misfire event within a 200-revolution or 1000-revolution test window. After two failed drive cycles, the code transitions from a pending to a confirmed DTC, and the PCM activates the MIL. Clearing the code without repairing the fault will result in re-illumination within one to two complete drive cycles.
Is It Safe to Drive?
An active P0220 code under high-severity conditions means the affected system is operating outside safe parameters. Continued driving — especially under load or at highway speeds — significantly increases the risk of secondary damage to components like faulty throttle body.
Mechanic's Pro Tip
The most common mistake with P0220 is replacing the sensor without verifying the reference voltage and ground integrity first. Use a scan tool to monitor the sensor's live output; a truly failed sensor shows a stuck, flatlined reading — a sensor that fluctuates but reads slightly off usually indicates a wiring or vacuum issue, not a dead sensor. Always spray electrical contact cleaner on the connector pins before condemning the sensor.
Pedal assembly: $150 - $350; Throttle body: $300 - $600