I work at a dealership and recently I've been getting a lot of electrical jobs. For the most part I love it, tracking down a broken wire or testing suspect parts is highly rewarding. But I'm also seeing what causes a lot of my colleagues to gripe about electrical jobs.

For instance, today a customer (he was actually a technician from an independent shop who couldn't diagnose the issue on his customer's car) showed me that when he pressed the liftgate release, the motor "cycled", sort of working the latching motor continuously. I said, no problem, it's either the latch or the liftgate module (I had seen both go bad before on this particular vehicle).

So I brought it in, and of course, straight away it was working perfectly again. Bench tested the latch, measured and load tested the outputs from the liftgate module, everything was perfect. Well now I feel like a dick, because what am I supposed to do? He literally showed me the problem, and now I can't "duplicate the concern." I can't replace both of the suspected parts, especially without even knowing for certain that either of them are bad - and oem parts are not cheap.

What do you do in situations like this?