NH3 Sensor Circuit
A general circuit fault on the NH3 (ammonia) sensor - measures ammonia slip downstream of the SCR catalyst to detect AdBlue overdose.
Affected components
- Nh3 sensor
Common causes
- High likelihood: Open in sensor or wiring
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.