Network, generic

U0119 Lost Communication With Fuel Cell Control Module

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

U0119 is the slot for losing the fuel cell control module, the controller that runs the hydrogen stack of a fuel cell vehicle: air compressor, hydrogen supply, humidity, stack cooling and the electrical output handed to the drive. Older code tables still label U0116–U0120 as reserved, so some scan tools show no text for it. No manufacturer documents the code publicly; Toyota, Hyundai and Honda have sold series fuel cell cars, yet their service data are not open. As a general frame, CARB asks for a dedicated code whenever a digital partner falls silent. U0468 covers invalid data from the same module, U0293 the hybrid/vehicle system controller. Once the link drops, the vehicle controller cannot request stack power: expect a system warning, operation only from the buffer battery or no READY.

Likely causes

Fuel cell controller without 12 V supply or ground
Damaged CAN wiring or connector between stack controller and vehicle controller
Software fault or missing update in one of the controllers
Fuel cell control module internally faulty

Symptoms

  • Fuel cell or drive system warning
  • Power limited to the buffer battery
  • Vehicle does not reach READY

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–3,000
Time1–6 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel cell modulecan bus wiring

Related codes

U0468U0293U0111

References: law.cornell.edu, en.wikipedia.org.