Throttle Position Sensor B signal wire shorted to a voltage source; Open ground or reference circuit for sensor B causing the signal to float high; Failed electronic throttle body assembly with an internal sensor fault; Corroded, loose, or backed-out terminals at the throttle body connector; Damaged wiring harness rubbed through against the engine or intake; Water intrusion into the throttle body connector or sensor housing; Rarely, a faulty engine control module driver on the sensor B circuit

DTC codes / P02xx · Fuel and air metering (injector circuits) / P0223

P0223Throttle Position Sensor B Circuit High Input

Q: What does code P0223 mean?

Throttle Position Sensor B Circuit High Input. P0223 means the engine computer has detected a high-voltage signal on the Throttle Position Sensor B circuit, which usually corresponds to the second throttle plate position sensor inside the electronic throttle body. The computer expects the two throttle position sensor signals to agree, and a sustained high input on sensor B tells it the circuit is shorted to voltage, open, or the sensor has failed internally.

P0223 means the engine computer has detected a high-voltage signal on the Throttle Position Sensor B circuit, which usually corresponds to the second throttle plate position sensor inside the electronic throttle body. The computer expects the two throttle position sensor signals to agree, and a sustained high input on sensor B tells it the circuit is shorted to voltage, open, or the sensor has failed internally.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illuminated check engine light, often with no other noticeable symptoms
Reduced engine power or limp mode with a sluggish throttle response
Hesitation or stumble when accelerating from a stop
Unstable or surging idle speed
Transmission may shift harshly or refuse to downshift because it relies on throttle position
Cruise control or traction control may be disabled

Common causes, most likely first

Throttle Position Sensor B signal wire shorted to a voltage source
Open ground or reference circuit for sensor B causing the signal to float high
Failed electronic throttle body assembly with an internal sensor fault
Corroded, loose, or backed-out terminals at the throttle body connector
Damaged wiring harness rubbed through against the engine or intake
Water intrusion into the throttle body connector or sensor housing
Rarely, a faulty engine control module driver on the sensor B circuit

How to diagnose and fix it

Scan all modules and record freeze-frame data for P0223 before clearing anything
Inspect the throttle body connector and harness for corrosion, chafing, or loose pins
Back-probe the sensor B signal wire and compare its voltage to sensor A through the full sweep of the throttle plate
Check the sensor B ground and 5-volt reference circuits for opens or excessive resistance
Wiggle-test the harness while watching live throttle position data to expose intermittent faults
If wiring and connectors pass, replace the electronic throttle body and perform the relearn or calibration procedure
Clear codes and verify the repair by running a full drive cycle with live data monitoring

Why sensor B rarely fails alone

On most electronic throttle bodies, sensor A and sensor B are wired as opposites, so a high B signal often means the computer sees an implausible relationship rather than a simple short.
A dirty throttle body can cause the two sensors to disagree at closed throttle and set P0223 even though the sensor itself is healthy.
Technicians who replace the throttle body without checking the 5-volt reference and ground circuits frequently get a repeat code because the real fault is in the harness.
P0223 can be set by a low battery or charging system spike that momentarily pulls the reference voltage out of range, so check system voltage before condemning parts.
Some vehicles require a throttle body adaptation or idle relearn after repair, and skipping it can leave the engine idling high or setting a companion code.

Can I keep driving with P0223?

You can usually drive the vehicle to a shop, but expect reduced power and poor throttle response, so avoid highway merging, heavy loads, and towing until the fault is repaired.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.