U061FLost Communication With Exhaust Gas Temperature Sensor Bank 1 Sensor 1
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- Many current exhaust temperature sensors are active: a thermocouple probe, often type N, feeds a small electronics module that turns the reading into SENT or CAN messages, as in the Sensience 22J sensor. U061F means valid messages from the bank 1, position 1 sensor (normally the most upstream one) have stopped. GM's 2025 diesel tables (25OBDG04A and 25OBDG04B) define it for a SENT sensor: any message fault, or messages that are too old, counted in 19 of 25 samples taken every 100 ms once the sensor start-up delay has passed and the engine is not cranking; Type A, so the MIL lights in the first trip. GM also stores a second code tied to the controller input the sensor is wired to. Bentley saw it with U0621 on 2020-on V8 Continental and Flying Spur cars whose harness chafed on a wheel-arch bracket.
- What you may notice
- Check engine or emission warning lamp
- Further codes for the controller input or the second bank
- Particulate filter regeneration may be postponed
- Likely causes
- LikelySensor harness rubbing through on a bracket or subframe edge (Bentley V8)
- PossibleConnector or module of the sensor damaged by exhaust heat
- PossibleInternal fault of the active sensor that shuts its SENT output off
- RareMissing 5 V supply or ground from the controller
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.