HomeTrouble CodesU3553

U3553 — Hydrogen Tank B Valve Control Circuit

Manufacturer-specificNetwork / communication

Code U3553 indicates a communication or electrical circuit failure related to the control valve for hydrogen storage tank B. This prevents the vehicle's control module from properly managing the flow of hydrogen from that specific tank to the fuel cell stack.

Symptoms

What causes it — most likely first

1. Faulty Tank B Valve Actuator

The internal electrical windings or solenoid within the valve have failed, creating an open or short circuit.

2. Wiring Harness Damage

The wiring between the control module and the valve is chafed, broken, or shorted to ground.

3. Connector Corrosion

Moisture or contaminants in the valve connector have increased resistance or broken the electrical connection.

4. Blown Fuse or Faulty Relay

The power circuit providing current to the valve actuator has been interrupted by a failed fuse or relay.

5. Fuel System Control Module Failure

The module responsible for sending the control signal to the valve is malfunctioning.

6. PCM/ECM Failure

The main engine computer has a failed output driver for the valve circuit.

How it's diagnosed

  1. Perform a full system scan to identify any accompanying network communication codes.
  2. Visually inspect the wiring harness leading to hydrogen tank B for signs of wear or physical damage.
  3. Inspect and clean the electrical connectors at the valve for corrosion or loose pins.
  4. Measure the resistance of the valve actuator using a multimeter to verify it is within factory specifications.
  5. Perform a voltage drop test on the circuit while the valve is commanded to operate.
  6. Check for power and ground at the actuator connector using a diagnostic test light or multimeter.

Code facts & related codes

SystemNetwork / communication
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Does this code mean the hydrogen tank is leaking?

No, U3553 is a circuit and communication code; it refers to the electrical control of the valve, not a physical leak in the tank.

Should I replace the PCM if I see this code?

No, this is rarely the cause. Most U3553 faults are found in the valve actuator or the wiring harness; the PCM should only be considered after all wiring and components are verified.

Can this be caused by using a different hydrogen refueling station?

No, refueling station compatibility does not affect the internal electrical circuit of the tank B control valve.