The U0125 code indicates that the vehicle's control modules have detected a loss of communication with the Multi-Axis Acceleration Sensor Module, which supplies motion data for stability and airbag systems.
The sensor itself can develop an internal fault that stops it from sending data on the CAN bus.
Broken wires, loose pins, or water intrusion in the sensor harness can interrupt the communication signal.
A short, open, or high-resistance condition elsewhere on the CAN network can cause messages to be lost.
A rare failure of the module that routes CAN traffic may also trigger the code, but it is usually the last suspect.
No, the PCM is rarely the cause; the issue is usually the sensor, its wiring, or the CAN network.
The vehicle may still operate, but stability, traction, and airbag functions could be disabled, so the problem should be addressed promptly.
Resetting may clear the warning light temporarily, but the code will return if the underlying communication fault remains.
Pricing varies by vehicle make and model, but it is typically less costly than replacing the entire PCM.