Before I arrived, an external contractor had diagnosed a machine fault as a failed DC motor.
The motor was removed.
Sent away.
Rewound.
Then eventually returned and refitted.
The bill was around £12,000.
There was just one problem.
The machine still wouldn't run.
At that point, it would have been easy to keep chasing increasingly complicated faults.
Instead, we went back to basics.
We stopped asking:
“What else has failed?”
And started asking:
“What if the original diagnosis was wrong?”
It didn't take long to find something interesting.
The contactors inside the power supply were badly worn.
They were arcing and causing intermittent faults.
The DC motor had never been the problem.
A replacement contactor kit costing around £600 was fitted.
The machine returned to service.
£12,000 had been spent repairing a component that wasn't faulty.
That experience reinforced something I've carried throughout my engineering career:
Never let somebody else's diagnosis become your fact.
As engineers, we're trained to solve technical problems.
As engineering leaders, we also need to make sure we're solving the right problem.
Because a bad diagnosis doesn't just cost money.
It costs production.
It costs time.
It damages confidence.
And it can send everyone further down the wrong path.
The biggest component isn't always the failed component.
The most expensive solution isn't necessarily the right solution.
And the first diagnosis isn't automatically the correct one.
Follow the fault. Not the assumption.
Sometimes the most valuable tool in engineering isn't a multimeter.
It's being prepared to ask:
“What if we're looking in the wrong place?”
Have you ever seen a costly repair carried out only to discover it wasn't the actual fault?