What should be prioritized before replacing a faulty module?

Prioritizing the availability of the correct spare module before replacement is crucial to ensure that the repair process can proceed smoothly and without unnecessary delays. If technicians replace a faulty module without confirming that the correct spare part is on hand, it could lead to a situation where the wrong module is installed, resulting in further complications or even system downtime. This step is central to effective maintenance practices, as having the correct spare ensures compatibility with the existing system and allows for immediate resolution of the issue.

In the context of the other options: assessing the entire system can provide valuable information about the fault but is often performed after ensuring that the right parts are available. Rebooting the system is a troubleshooting step that may sometimes resolve issues, but it does not address the underlying fault if a module must indeed be replaced. Updating the control software could be relevant for other types of troubleshooting or upgrades, but it is generally advisable to replace physical components, such as modules, based on the correct spare being available first.