U067ELost Communication With Exhaust Pressure Control Valve B Sensor/Switch
- Generic OBD-II code · Network
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- An exhaust pressure control valve is a flap in the exhaust that diesels close partly to raise back pressure, which speeds warm-up and helps reach filter regeneration temperatures. Valve B is a second flap of this kind, and U067E concerns its position sensor or switch when that reports digitally: the controller has lost its messages. Public manufacturer documentation for U067E is lacking. GM's 2025 diesel table 25OBDG04B shows the pattern for valve A, a SENT position sensor whose silence gives U0650 after 480 failed checks out of 600 at 6.25 ms, Type A. For valve B, drive faults run from P049F to P04A5 and analog position faults from P04A6 to P04AA. CARB wants a separate code for a mute digital input. Warm-up and regeneration may be impaired.
- What you may notice
- Check engine light
- Particulate filter regeneration delayed or not started
- Longer warm-up in cold weather
- Likely causes
- LikelySensor wiring at valve B damaged by exhaust heat
- PossibleConnector at valve B corroded or loose
- PossiblePosition sensor in the valve B unit failed
- RareEngine controller input or software fault
- 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: €60 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.