What would cause a network error message indicating one module is offline?

The situation described, where a network error message indicates that one module is offline, is likely due to a high resistance issue at the module power connection. In a vehicle's networked system, each module requires a stable power supply to operate correctly and communicate with other modules.

If there is high resistance present at the power connection, it may prevent the module from receiving adequate voltage or current, leading to erratic performance or complete failure to operate. As a result, the network may register the module as offline. This scenario highlights the importance of ensuring that all connections are clean and secure, as high resistance can create a critical failure point in communication between modules.

In contrast, an open network harness fuse or an open backbone wiring harness would lead to a broader failure of network communications across multiple modules, rather than isolating a single module. Excessive network signal traffic could lead to latency issues but would not typically result in an offline message for just one module unless it is overwhelmed to the point of malfunction.