U0105 code meaning
Lost Communication With Fuel Injector Control Module
Network system Generic code U01xx codes Check engine light
What U0105 means
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.
U0105 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0105
- MIL on
- Misfire, rough running or reduced power
- Engine stalls or will not start
Common causes of U0105
- Most likelyInjector module supply low or missing (fuse, relay, battery voltage)
- PossibleLoose or corroded connector or damaged CAN lines to the module
- PossibleInjector module internally faulty (heat, power stage)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel injector control moduleCAN bus wiring
What each part of U0105 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 05 | The exact fault in that area. |
What to do next
- Note U0105 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0105
What does U0105 mean?
U0105 means "Lost Communication With Fuel Injector Control Module". U0105 concerns a separate fuel injector control module that drives the injectors on command of the engine controller. It is a generic code, so it means the same on every make.
Is it safe to drive with U0105?
Drive gently and only to a workshop. With U0105 the car can go into limp mode (reduced power) to protect itself.
Will U0105 fail an emissions test?
Yes, it can. U0105 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0105 to fix?
Difficulty: hard. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will U0105 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.