OBD-II code · Network
U029F Lost Communication With Evaporative Emission System Leak Detection Control Module
The vehicle bus reports loss of communication with the EVAP leak detection module. Tank-pressure / vacuum diagnostics for fuel-vapour leaks cannot be commanded.
Is it safe to drive with U029F?
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
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Evap Leak Detection Module, Vehicle Bus Wiring
Related codes
- U029CLost Communication With Drive Motor Control Module D
- U029DLost Communication With NOx Sensor A
- U029ELost Communication With NOx Sensor B
- U02A0Invalid Data Received From Hybrid/EV Battery Interface Control Module D
- U02A1Lost Communication With NOx Sensor C
- U02A2Lost Communication With Reductant Quality Module
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.