OBD-II code · Network (extended)
U3555 Hydrogen Tank B Valve Performance
Hydrogen Tank B Valve Performance: the component is electrically intact but its response does not match the command.
Is it safe to drive with U3555?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyValve stuck mechanically
- 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
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–8 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- H2 Tank B Valve
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.