P24EANH3 Sensor Supply Voltage Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- The NH3 sensor is a smart unit: its electronics module needs its own power feed, usually switched battery voltage through a fuse or relay, to run the probe, the heater and the J1939 link. P24EA is the general fault of that supply, set when the measured feed voltage is missing, unstable or otherwise outside the valid window without being classed as clearly low or high. Navistar describes this type of module on the 2013 N13 as one that runs its own internal checks and reports them over the data link, which only works with clean power. No manufacturer publishes P24EA. CARB expects heavy-duty OBD to catch circuit faults on such components. P24EB and P24EC are the low and high cases.
- What you may notice
- Check engine light on
- Further NH3 sensor or communication codes stored
- Likely causes
- LikelyFuse or relay in the sensor feed faulty or loose
- PossibleDamaged or corroded power or ground wire to the sensor module
- RareSupply monitoring in the sensor module defective
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.