P0222: Throttle/Pedal Position Sensor/Switch B Circuit Low Input
The P0222 code indicates that the Engine Control Module (ECM) has detected a low voltage signal from the throttle position sensor (TPS) or accelerator pedal position sensor (APP) circuit B. This sensor is critical for determining driver demand and throttle angle. A low input typically means the signal voltage is below the expected range (usually below 0.2-0.5V), which can be caused by a faulty sensor, wiring issues, or a defective ECM. This code often triggers reduced engine power mode (limp mode) to prevent unsafe operation.
01. Most Common Causes
- Faulty throttle position sensor (TPS) or accelerator pedal position sensor (APP)
- Open or shorted wiring in the sensor circuit B
- Poor electrical connection at the sensor or ECM connector
- Failed ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power (limp mode) with limited acceleration
- Poor throttle response or hesitation
- Engine stalling or rough idle
03. Step-by-Step Diagnosis
Step 1: Connect an OBD2 scanner and verify the code P0222. Check for additional codes like P0122 or P0223.
Step 2: Visually inspect the TPS/APP sensor wiring and connectors for damage, corrosion, or loose pins.
Step 3: Using a multimeter, check the reference voltage (typically 5V) and ground at the sensor connector. Then measure the signal voltage from circuit B while slowly pressing the accelerator pedal; it should vary smoothly from ~0.5V to ~4.5V.
Step 4: If signal voltage is stuck low or erratic, replace the sensor. If wiring is faulty, repair or replace the harness.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with P0222 because the vehicle may enter limp mode, limiting speed and acceleration, which can be dangerous in traffic. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for a DIY sensor replacement. Professional repair including diagnosis and labor may cost $150 to $300 or more, depending on the vehicle and shop rates.