- Is it switched on (Yeah, I know, it's obvious but it can be missed)?
- Is there power? If not, is the fuse or circuit breaker good? (If in doubt, trip & reset)
- Is the control circuit operating correctly?
- Are the jumpers between vehicles fitted properly?
Simple things like these can often cause a lot of unnecessary delay. They should always be checked first. On the other hand, there might be a series of unexplained failures on one piece of equipment or one type of train. Although the route to solving the problem is different, the approach to finding it should be the same:
- Is the problem only on one type of equipment?
- Is it only on one type of train or unit or different types?
- Is it on one type of formation (freight or passenger)?
- Does it occur on every route or just one?
- Does it occur only in one type of weather or season, e.g. very cold or very hot?
- Has something changed recently - maintenance procedures, operating procedures, type of traffic carried?
- Has the maintenance been done as and when it should?
- Has the staffing changed recently - often an issue when someone new comes in.
- What else is different?
This approach will give valuable pointers to finding the cause and probably the cure and it may save you a lot of money.