U0468: Invalid Data Received From Fuel Cell Control Module

What it means

A receiving module detected implausible data from the fuel cell control module (FCEV stack manager). Stack voltage, current or hydrogen flow values fail plausibility checks and are rejected.

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

The fuel cell control module manages the fuel cell stack and reports operating data such as stack voltage, current, and hydrogen flow to other modules. A receiving module sets U0468 when those values fail plausibility checks and are rejected.

Common causes

Most likely first.

1. Module internal fault or sensor input drift
2. Software version mismatch after replacement
3. Gateway module routing CAN messages incorrectly

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. Read all vehicle and fuel-cell system codes and save freeze-frame data to identify the receiving module and the conditions when it rejected stack data.
2. Check the instrument display for fuel-cell, hydrogen-system, or reduced-power warnings and compare available live stack voltage, current, and hydrogen-flow data for plausibility.
3. Visually inspect accessible low-voltage connectors and harnesses at the fuel cell control module for damage, water intrusion, or loose connections; do not disturb high-voltage or hydrogen components.
4. Check for related CAN or gateway communication faults and confirm whether multiple modules report missing or implausible fuel-cell data.
5. Have the manufacturer's diagnostic procedure used to verify stack sensor inputs, control-module software compatibility, and the fuel-cell module itself.

Common fixes

• Repair a damaged or poorly connected low-voltage harness or connector identified in diagnosis.
• Correct a low-voltage power, ground, or network connection fault.
• Update or configure a replacement fuel cell control module to the vehicle's specification.
• Repair or replace a faulty sensor input or fuel cell control module as confirmed by testing.

Can I keep driving?

Because this fault can trigger reduced power or a fuel-cell system shutdown, avoid driving if a warning is displayed or propulsion is limited; arrange a safe stop if power drops unexpectedly. Do not attempt repairs on high-voltage or hydrogen components yourself.