OBD-II code · Network
U0668 Lost Communication With Engine Oil Level Sensor Circuit
The vehicle bus reports loss of communication with smart engine oil level sensor. Oil-level warnings cannot be issued reliably; refill alerts may be missing.
Is it safe to drive with U0668?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
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
- 0.5–2 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Engine Oil Level Sensor, Vehicle Bus Wiring
Related codes
- U0665Lost Communication With Fuel Rail Pressure Sensor Bank 2
- U0666Lost Communication With Reductant Pressure Sensor
- U0667Lost Communication With Engine Oil Temperature Sensor A
- U0669Lost Communication With EGR Sensor D
- U066ALost Communication With EGR Sensor E
- U066BLost Communication With Turbocharger/Supercharger Bypass Valve B Position Sensor
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.