This baby came in for a little inspection this week. The owner was worried that it was a ticking time bomb, as the start sequence would randomly take longer some days and not others. He mentioned, when cold, the unit could take 7-to 15 relay clicks to start. When warm and operating normally he would hear 3-5 relay clicks.
I was able to experiences this extended start up the first time I turned it on, I counted 7 clicks, but it did start. I turned it off and back on, and it took three clicks to boot.
I took it apart, and have to say it is a pretty well thought out design. Clearly significant thought went into the manufacturability and repair of the unit. Someone had already been inside, as I found a broken screw and several stripped machine screws.
Inside this is what I saw:
Lots of ribbons and tight interconnection wiring. The clicks were coming from two relay control boards.
I could not tell exactly what relays were clicking in by ear, but certainly the wiring was tight.
I removed the ribbons one by one and inspected the pins, no really signs of oxidation or corrosion. I reseated them a few times. I restarted the unit cold and no real change, it still started slow.
I then removed the cable interconnects and inspected the connectors, nothing clearly visible. I reseated the connectors a few times. And retried the unit. 4 clicks to start...hum maybe it was warm. I let it cool down a bit. My garage is not heated so 15 mins later I tried it, 4 clicks again. Could that be all it was?
I am not sure if that is truly all it was, but I put it back together. And will try again today...
Comments
That all looks reasonably OK. Can you reproduce the condition
That all looks reasonably OK.
Can you reproduce the condition that had the irregular number of start-up clicks? Maybe it simply did require re-seating of connectors, although that wouldn't be the first time that going though a re-seating process has cured mysterious irregular and intermittent problems.
Did you manage to check what the power rails were doing during t
Did you manage to check what the power rails were doing during the abnormal clicking start-up?