U0250 indicates that the vehicle's control network has lost communication with the Impact Classification System Module (ICSM), a component that works with the airbag and crash‑sensing system to determine crash severity. When the module cannot be reached on the CAN bus, the PCM/ECM logs this network fault code.
Corrosion, chafing, or loose pins in the harness linking the module to the CAN bus can interrupt communication.
Internal electronics failure within the module prevents it from transmitting or receiving messages on the network.
Blown fuse, weak battery voltage, or poor ground connection can cause the module to drop off the bus.
A problem elsewhere on the CAN network (e.g., bad termination resistor, shorted bus, or another module pulling the bus low) can block communication with the ICSM.
The ICSM's firmware may become corrupted, causing it to ignore bus traffic until re‑programmed.
While the PCM/ECM could theoretically fail to send/receive the proper network signals, this is uncommon and should be considered only after all wiring, module, and bus checks are completed.
No. The PCM/ECM is rarely the cause of this code. Most U0250 faults are due to wiring, connectors, the Impact Classification System Module itself, or CAN‑bus issues. Only consider the PCM/ECM after all those possibilities have been ruled out.
Yes. If the fuse that supplies power to the Impact Classification System Module is open, the module will lose power and drop off the CAN bus, triggering the code.
While the vehicle may still run, safety systems that rely on the Impact Classification System (such as side‑airbag deployment thresholds) may not function correctly. It is advisable to have the issue diagnosed and repaired promptly.
Clearing the code only removes the stored fault; if the underlying communication issue remains, the code will return shortly after the next drive cycle.