P0712Transmission Fluid Temperature Sensor A Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- The transmission fluid temperature sensor is an NTC thermistor whose resistance falls as the fluid warms; the module feeds it with 5 V through a resistor. A low signal therefore means very hot or a short to ground, a high signal very cold or an open circuit. P0712 means the signal is too low – the sensor reads extremely hot, or the signal wire is shorted to ground. GM's 2025 transmission modules flag below 13.5 Ω for 5 of 6 s after two trips; the 2018 LT4 engine module below 17.88 Ω (over 150 °C) without MIL; the 2007 Allison 1000 150 °C or more for 2.5 s; Saab's AF40 over 200 °C; Ford below 0.05 V for 5–12 s without MIL. The module substitutes a value (coolant temperature, 80 °C or a hot mode) and may shift with hot-fluid strategy. Real overheating with a good sensor is P0218.
- What you may notice
- Transmission in hot mode (early converter clutch, changed shift points)
- Harsh shifts
- Extremely high fluid temperature shown
- Check engine or transmission lamp depending on manufacturer
- Likely causes
- LikelySignal wire shorted to ground (internal harness, chafing)
- PossibleSensor shorted internally
- RareTransmission actually severely overheated
- RareControl module faulty
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.