Network, generic

U0105 Lost Communication With Fuel Injector Control Module

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

U0105 concerns a separate fuel injector control module that drives the injectors on command of the engine controller. GM's 2005 Duramax 6.6 L (LLY) received a status message from this injector driver via CAN (J1939) whose toggle bit must flip every 20 ms; if it stalls for three updates, 30 failures in 50 checks give a Type B code. On the 2019 Corvette LT5 the ECM watches frame $1EA from a dedicated injector module and, after 10 s without it, logs U0105 as Type A on the first trip. Losing this link usually means misfire, power reduction or a stall, since the ECM can no longer confirm injection. U0406 covers invalid data and U0306 a software mismatch with the same module.

Likely causes

Injector module supply low or missing (fuse, relay, battery voltage)
Loose or corroded connector or damaged CAN lines to the module
Injector module internally faulty (heat, power stage)

Symptoms

  • MIL on
  • Misfire, rough running or reduced power
  • Engine stalls or will not start

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,500
Time1–5 h

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

Parts involved

fuel injector control modulecan bus wiring

Related codes

U0100U0306U0406

References: gsi.ext.gm.com, gsi.ext.gm.com, law.cornell.edu.