OBD-II code · Network (extended)
U350C Control Module Cooling Fan Circuit/Open
Open circuit at the control module cooling fan (used to keep heavy ECUs like ADAS compute or inverter controllers within thermal limits).
Is it safe to drive with U350C?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyFan motor open
- Less likelyGateway module routing CAN messages incorrectly
- Less likelyCAN terminating resistor (120 Ω) drifted out of spec
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
- Often, with basic tools
- Typical labour
- 0.5–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Module Cooling Fan, Fan Wiring
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.