What this code means

NOx sensor on bank 1 is responding but values are outside expected range.

Symptoms

• Check engine light
• Poor emissions performance
• Possible SCR fault codes

Common causes

• Degraded NOx sensor
• Exhaust leak near sensor
• Contaminated sensor element

Diagnostic steps

1. Compare actual NOx levels to expected at various loads
2. Check for exhaust leaks
3. Inspect sensor condition

Repair notes

Replace NOx sensor if out of specification after leak check.

Other Powertrain codes on this vehicle