P0112Intake Air Temperature Sensor 1 Circuit Low Bank 1
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Intake air temperature sensor 1 is the first air temperature sensor in the intake path; depending on the vehicle it is built into the mass air flow sensor, mounted near the air filter or, on some naturally aspirated GM engines, fitted in the intake manifold. Most versions are NTC thermistors in a 5 V divider: the hotter the air, the lower the signal voltage. P0112 means the signal is below its valid range. With an NTC sensor that points to a short to ground in the signal wire or an internally shorted sensor, and the control module would read an implausibly hot value (GM about 150 °C). Documented limits: Ford petrol below 0.244 V for 5 s, Ford diesel below 0.10 V, GM below 62 ohms. The circuit is monitored continuously; GM needs two trips. Some systems then use the coolant temperature, capped at 40 °C, as a substitute and limit torque.
- What you may notice
- Check engine light on
- Usually hardly noticeable
- Retarded ignition, reduced power or torque limit on some systems
- Harder cold start possible
- Likely causes
- LikelySignal wire shorted to ground (chafed insulation)
- LikelySensor shorted internally
- PossibleMoisture or corrosion in the connector
- RareEngine control module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €30 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.