Throttle/Pedal Position Sensor/Switch B Circuit Malfunction
The throttle position sensor circuit B is malfunctioning, meaning the sensor isn't properly communicating throttle position to the engine control module. This prevents the engine from accurately adjusting fuel and ignition timing based on driver input, causing drivability issues.
What You Might Notice
- Check engine light illumination
- Misfiring at idle or highway speeds
- Poor idle quality or rough idling
- Engine stalling after starting
- Hesitation during acceleration
Most Common Causes
- 1
Throttle Position Sensor failure
The TPS potentiometer has degraded or failed electrically, preventing accurate throttle position reading. This is the most common cause of P0220.
- 2
TPS connector corrosion
Corroded or loose connectors on the throttle position sensor prevent proper electrical signal transmission to the PCM.
- 3
Sticking throttle return spring
The spring that returns the throttle to idle position is stuck or binding, causing erratic sensor readings and poor throttle response.
- 4
Damaged or misrouted wiring harness
Harness chafing, breaks, or incorrect routing between the TPS and PCM disrupts the circuit signal integrity.
How to Diagnose It
- 1
Check Throttle Position Sensor failure — The TPS potentiometer has degraded or failed electrically, preventing accurate throttle position reading. This is the most common cause of P0220.
- 2
Check TPS connector corrosion — Corroded or loose connectors on the throttle position sensor prevent proper electrical signal transmission to the PCM.
- 3
Check Sticking throttle return spring — The spring that returns the throttle to idle position is stuck or binding, causing erratic sensor readings and poor throttle response.
- 4
Check Damaged or misrouted wiring harness — Harness chafing, breaks, or incorrect routing between the TPS and PCM disrupts the circuit signal integrity.
How to Fix It
- 1
Replace throttle position sensor
Remove the old TPS from the throttle body and install a new one, ensuring proper connector seating. Perform throttle relearn procedure with diagnostic scanner afterward.
- 2
Clean or replace TPS connector
Disconnect the TPS electrical connector and inspect for corrosion. Clean with electrical contact cleaner or replace the connector if severely corroded.
- 3
Inspect and free stuck throttle linkage
Check that the throttle return spring moves freely and isn't binding. Clean any debris and apply appropriate lubricant to restore smooth throttle operation.
- 4
Repair wiring harness and PCM connection
Inspect the TPS circuit harness for damage, chafing, or misrouting. Repair or replace damaged sections and ensure proper connector seating at the PCM.
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