U3565: Hydrogen Supply Line A Pressure Sensor 2 Circuit

What it means

Generic fault on the pressure sensor 2 in hydrogen supply line A — feeds the fuel cell anode after the tank's pressure regulator.

At a glance

• Usually lights the warning light of the system that lost communication

How it works

Hydrogen supply line A pressure sensor 2 measures pressure in the line that feeds the fuel-cell anode downstream of the tank regulator. The control module monitors sensor 2 specifically and sets this code when its circuit or communication path prevents reliable pressure data.

Common causes

Most likely first.

1. Sensor failed
2. Gateway module routing CAN messages incorrectly
3. 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

1. Record freeze-frame data and scan all relevant modules for related hydrogen pressure and communication faults.
2. Compare live data from line A pressure sensor 2 with sensor 1 and the fuel-cell operating state to identify a missing or implausible reading.
3. Inspect sensor 2's connector and accessible wiring for looseness, corrosion, moisture, or damage without opening or disturbing the hydrogen line.
4. Check sensor 2's power, ground, and signal circuits against the manufacturer's specification.
5. If communication faults affect other modules, have gateway routing and CAN network integrity checked to the manufacturer's specification.

Common fixes

• Repair loose or damaged wiring to hydrogen supply line A pressure sensor 2.
• Clean or repair corroded terminals at sensor 2.
• Replace sensor 2 if electrical checks pass but its pressure data remains faulty.
• Repair a confirmed gateway or CAN network fault.

Can I keep driving?

Stop safely and do not continue driving if a hydrogen leak warning, fuel-cell shutdown warning, or major power loss occurs. Otherwise, limit demanding use and arrange prompt diagnosis; avoid touching or opening hydrogen system components.