OBD-II code · Network
U0659 Lost Communication With Left Front Temperature Actuator
The vehicle bus reports loss of communication with smart left-front HVAC temperature blend door actuator. Driver-side air temperature falls back to a default position.
Is it safe to drive with U0659?
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
- Lf Temp Actuator, Vehicle Bus Wiring
Related codes
- U0656Lost Communication With Turbocharger/Supercharger Boost Control A Position Sensor
- U0657Lost Communication With Turbocharger/Supercharger Bypass Valve A Position Sensor
- U0658Lost Communication With Windshield Temperature Sensor
- U065ALost Communication With Right Front Temperature Actuator
- U065BLost Communication With Left Front Mode Actuator
- U065CLost Communication With Right Front Mode Actuator
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.