OBD Guide

P2203

NOx Sensor Circuit High Bank 1 Sensor 1

P2203 is an OBD-II diagnostic trouble code meaning: NOx Sensor Circuit High Bank 1 Sensor 1. Common causes: nox bank 1 sensor 1 malfunction, open or short circuit in the sensor circuit. Estimated repair cost: $89–278.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$89–278 (est.)

Symptoms

  • Check Engine Light Is On
  • Reduced engine power
  • Increased fuel consumption
  • Unstable engine idling
  • SCR errors (if this system is installed)

Causes

  • NOx Bank 1 Sensor 1 malfunction
  • Open or short circuit in the sensor circuit
  • Connection problems or connector corrosion
  • ECM malfunction
  • Real NOx levels exceeded due to problems with the SCR or EGR system

How to Fix

  1. Check the integrity of the NOx sensor wiring and connectors
  2. Check the power supply and grounding of the sensor circuit
  3. Compare sensor readings with reference values
  4. If necessary, replace the NOx sensor
  5. Check the functionality of the SCR system (if installed)

Related codes

Error P2203 by Vehicle Brand

FAQ

What does the P2203 code mean?

P2203 is an OBD-II diagnostic trouble code that indicates: NOx Sensor Circuit High Bank 1 Sensor 1

What causes a P2203 error code?

The most common causes of P2203 include: NOx Bank 1 Sensor 1 malfunction; Open or short circuit in the sensor circuit; Connection problems or connector corrosion; ECM malfunction.

How do I fix a P2203 diagnostic trouble code?

To fix P2203: Check the integrity of the NOx sensor wiring and connectors. Check the power supply and grounding of the sensor circuit. Compare sensor readings with reference values. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P2203?

Yes, but get it checked soon

How much does it cost to fix P2203?

The estimated repair cost for P2203 is $89–278. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat