What it means
A control module has lost communication with the fuel injector control module. Engine operation may be affected if the vehicle uses this module; the code alone does not establish a particular failure symptom.
How it works
The fuel injector control module operates or coordinates fuel injector circuits on vehicles equipped with a separate module. It sends operating information to other modules over the vehicle network. U0105 sets when a reporting module stops receiving expected messages from the fuel injector control module.
Common causes
Most likely first.
- Loss of module power or ground
- Open, shorted, or damaged communication wiring or connector
- Module or gateway fault
Symptoms
- Warning lights or messages
- Communication faults in other modules
- Engine starting or running problems may occur
How to diagnose it
- Scan all modules for U0105 and related powertrain or network codes, and save freeze-frame details before clearing anything.
- Note whether the engine starts, runs smoothly, or loses power, and check whether injector-module data is available on the scan tool.
- Inspect the fuel injector control module connector and harness for corrosion, loose terminals, heat damage, or chafing.
- Check the module's power and ground circuits under the captured operating conditions against the manufacturer's specification.
- Test its communication wiring for opens, shorts, or poor connections using the vehicle wiring diagram.
- If the module has sound power, ground, and network connections, use vehicle-specific diagnostics to check gateway and module operation.
Common fixes
- Repair a loose or corroded fuel injector control module connector.
- Repair damaged wiring or a poor ground at the module.
- Restore the module's power supply and correct the cause of any blown fuse.
- Repair a gateway or network fault if testing confirms it.
- Replace or program the fuel injector control module only after its supply and communication circuits pass testing.
Can I keep driving?
If the engine runs normally, drive only as needed to reach a safe location for diagnosis; avoid hard acceleration and long trips. If it stalls, misfires severely, or will not restart, do not continue driving because loss of injector control can leave the vehicle without reliable power.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.