OBD-II code · Network
U0674 Lost Communication With Wastegate Position Sensor B
The vehicle bus reports loss of communication with smart wastegate position sensor B. Closed-loop wastegate control loses its actual feedback; boost falls back to an open-loop fail-safe.
Is it safe to drive with U0674?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyBus wiring open or shorted
- PossibleModule without power or ground
- PossibleModule failed
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Wastegate Position Sensor B, Vehicle Bus Wiring
Related codes
- U0644Lost Communication With Wastegate Position Sensor A
- U0671Lost Communication With Fuel Temperature Sensor B
- U0672Lost Communication With Engine Coolant Pump
- U0673Lost Communication With Ion Sense Module
- U0675Lost Communication With Turbocharger/Supercharger Speed Sensor A
- U0676Lost Communication With Fuel Level Sensor A
- U0677Lost Communication With Fuel Level Sensor B
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.