OBD-II Code P0223 — What It Means & How to Fix It

What Does This Error Mean?

P0223 means the ECM has detected a higher-than-expected voltage signal from throttle position sensor B. Unlike P0222 (too low), this code means the sensor signal voltage is stuck high — often above 4.5 volts — when it should vary as the throttle opens and closes. This usually points to a shorted signal wire, a failed sensor, or a wiring fault that is pulling the signal voltage up. You may notice hesitation, limp mode, erratic throttle response, or poor acceleration.

Affected Models

All 1996+ vehicles with electronic throttle control
Common in Toyota, Honda, Ford, GM, and Chrysler platforms
Frequently seen in high-mileage vehicles
Common after throttle body cleaning if connectors were disturbed
Vehicles with rodent-chewed wiring harnesses

Common Causes

Throttle position sensor B is internally shorted, sending a fixed high voltage
Signal wire for TPS B is shorted to the 5-volt reference wire
Damaged wiring harness with TPS signal wire exposed and contacting 5-volt line
Connector pins bent or bridged together, creating a false high voltage reading
Failed throttle body with an integrated sensor that cannot be replaced separately

How to Fix It

Check for related codes such as P0222 (TPS B low voltage), P0221 (TPS B performance), and P2135 (TPS A/B correlation). Multiple TPS codes together point to a sensor or throttle body issue.

If only P0223 appears alone, a wiring short is more likely than a sensor failure.
Inspect the TPS wiring connector. Look for bent pins that could be touching adjacent pins, moisture bridging pins, or signs of chafing where the harness runs against the engine.

Rodent damage to engine wiring is surprisingly common — check the entire harness for bite marks.
Disconnect the throttle body connector and recheck the TPS B signal voltage at the harness side with the key on. If the voltage drops to zero with the connector unplugged, the short is in the sensor. If it stays high, the short is in the wiring.

This test quickly tells you whether the fault is the sensor itself or the wiring leading to it.
If the short is in the wiring, trace the TPS B signal wire through the harness looking for damage. Repair any damaged sections with proper automotive wire splice connectors and heat shrink.

Never use household electrical tape for engine wiring repairs — it deteriorates quickly from heat and moisture.
If the fault is in the sensor or throttle body, replace the throttle body assembly. Perform a throttle body relearn procedure if required by your vehicle.

On many vehicles, the idle control strategy must relearn after throttle body replacement — consult your repair manual.

When to Call a Professional

High voltage TPS faults can be caused by a wiring short that could damage the ECM if left unresolved. A professional can quickly backprobe the connector with a multimeter to confirm whether the signal wire is shorting to another circuit. Throttle body replacement — necessary when the sensor cannot be replaced separately — benefits from a shop that can perform the required relearn procedure.

Frequently Asked Questions

Is P0223 worse than P0222?

Neither is necessarily worse — both indicate the throttle position sensor circuit is not reading correctly. P0223 (high voltage) can sometimes indicate a more serious wiring short that could affect other circuits. Both codes will typically trigger limp mode and reduce throttle response for safety. Get either code diagnosed promptly.

Can a dirty throttle body cause P0223?

Carbon buildup in the throttle body affects airflow and idle quality but rarely causes high voltage sensor codes on its own. P0223 is an electrical fault — the sensor or wiring is sending incorrect data. Cleaning the throttle body is worth doing during diagnosis, but it is unlikely to fix a high voltage code.

How much does it cost to fix P0223?

If the cause is a damaged connector or wiring short, repairs can cost $50 to $150 at a shop. If the throttle body needs replacement, expect $150 to $450 for the part and labor. Always have the root cause confirmed before replacing parts — wiring repairs are much cheaper than a new throttle body.