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P2203 Fuel & Air Metering
NOx Sensor Circuit High Bank 1
P2203 means the NOx sensor circuit on Bank 1 is reading a voltage that is too high. This typically points to an open circuit, a short to voltage, or a failed sensor.
🚗 Yes, short-term, but have it checked soon.
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🎯 Top Causes, Ranked by Likelihood
#1 Failed NOx sensor $200-$700
An internal fault drives the signal high.
#2 Open circuit in wiring $50-$300
A break in the harness raises the read voltage.
#3 Short to voltage $50-$300
The signal wire contacts a power source.
#4 Control module fault $300-$1000
Rarely, the module misreads the input.
🩺 Common Symptoms Check engine light Reduced engine power Failed emissions test Possible limp mode 💰 Repair Cost: DIY vs Shop
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🔧 How to Diagnose P2203 1 Inspect NOx sensor wiring for opens or shorts to power
2 Check the connector and pins
3 Measure the circuit voltage with a meter
4 Replace the NOx sensor if confirmed
❓ Frequently Asked Questions Can I drive with P2203?
Short-term yes, but repair it soon to avoid limp mode and emissions failure.
How much to fix P2203?
Typically $400-$1000 at a shop including the sensor.
What causes P2203 most often?
A failed NOx sensor or an open circuit in the wiring.
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