U0228 indicates that the Powertrain Control Module (PCM) has lost communication with the door/window motor control module designated as 'G'. This means the PCM is not receiving the expected signals from that motor controller.
Damage, corrosion, or pinched wires in the harness that runs between the PCM and the door/window motor controller can interrupt the communication signal.
Loose, dirty, or corroded pins in the connector, or a bad ground strap, can cause intermittent loss of communication.
The motor controller itself may have an internal fault that prevents it from responding to PCM requests.
A shorted motor winding or failed driver transistors inside the module can stop the module from communicating.
Only after ruling out wiring, connectors, and the motor controller should the PCM’s communication circuitry be considered, as this is an uncommon cause.
Clearing the code may turn off the warning temporarily, but if the underlying communication failure remains, the code will return.
No. In the overwhelming majority of cases the fault is in the wiring, connector, or the door/window motor controller itself. PCM replacement is only considered after all other possibilities have been eliminated.
A fuse that protects the communication circuit can cause loss of signal, but most vehicles use fused power lines separate from the data bus. Verify fuse status, but it is not the primary cause.
U0228 is specific to the G‑designated module, usually a single window. However, a wiring harness fault in a shared harness could affect adjacent windows, so inspect related circuits.