What it means
Hydrogen Tank B Valve Control Circuit: the control circuit has an electrical fault.
At a glance
- Usually lights the warning light of the system that lost communication
- The engine or gearbox may go into limp mode
How it works
Tank B’s valve solenoid is electrically controlled to regulate hydrogen flow from that tank. This code indicates an electrical fault in the Tank B valve control circuit, which may prevent the controller from operating the solenoid correctly.
Common causes
Most likely first.
- Valve solenoid failed
- Gateway module routing CAN messages incorrectly
- CAN 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
How to diagnose it
- Save freeze-frame data and scan all modules for related communication or power-supply codes before clearing anything.
- Check live data for the Tank B valve command and status, if available, and note whether the fault appears with the command or persists continuously.
- With the vehicle safely powered down under its service instructions, inspect the Tank B solenoid connector and control-circuit wiring for corrosion, looseness, chafing, or damage.
- Check the relevant fuse, supply, ground, and circuit continuity using the manufacturer’s wiring diagram and specification.
- If several modules report communication faults, have a technician check gateway routing and CAN network condition, including termination against the manufacturer’s specification.
- If the circuit and network test correctly, test the Tank B valve solenoid according to the manufacturer’s procedure.
Common fixes
- Reconnect or repair damaged Tank B valve control wiring or terminals.
- Replace a failed fuse or repair a poor circuit ground or supply connection.
- Correct a gateway routing fault or repair the CAN network if tests identify one.
- Replace the Tank B valve solenoid if it fails the specified circuit test.
Can I keep driving?
A Tank B valve control fault can lead to reduced power or fuel-cell system shutdown, so avoid unnecessary driving and stop safely if the vehicle’s power or warnings worsen. Arrange prompt service and leave hydrogen-system components to qualified technicians.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.