Network
generic or reserved
U3551
Hydrogen Tank A Valve Enable Circuit
Fault on the enable line that authorises the hydrogen tank A valve to open. Used as redundant safety release.
SystemNetwork
Typegeneric or reserved
GroupU3
Range / number5 / 51
Possible causes
- Enable wire open or relay failed high
- Gateway module routing CAN messages incorrectly low
- CAN terminating resistor (120 Ω) drifted out of spec low
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
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 200–2000 €
- Estimated time: 1–5 h
- Component: h2 tank a valve enable
- Component: safety circuit
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012