I'm hoping that the Pinside hive mind can provide me with a sanity check, because I don't always trust my troubleshooting skills and this one is driving me nuts.
Backstory: My otherwise fully working Sorcerer had a single display out, so I wanted to replace it with a PinScore system. That part was straightforward enough, and within a few minutes I got that problem resolved. But then I noticed that one string of GI lights on the backbox was out. This was most certainly not the case as I had just taken some pictures a week or two ago that show that everything works. Here is what I did to try to figure out the problem:
- Measure voltage across any lamp socket on the non-working GI string confirms that there is nothing there
- Switch out a few bulbs to rule out that somehow all of them burned out at the same time. There were a few burned ones but most of them work fine
- Replace power board with brand new XPin one (which was on the todo list so now is a good time as any) The connector to the power board with the 4 GI lines does show some signs of being toasted - so this will get replaced asap
- Measure voltage at connector on power board - OK
- Measure voltage at connector to the GI lights - OK
- Disconnect connector, remove all the bulbs from the non-working GI string, measure connectivity, there appears to be a short. Reconnect connector, measure voltage, still nothing there
- Disconnect connector, remove all the bulbs from the working GI string, measure connectivity, appears to be open. Reconnect connector, measure voltage, OK
My thinking now is that without any bulbs in place there should not be any connectivity between the 2 GI lines. The presence of a short would explain why there's no voltage and nothing lights up in that string. So my next steps should be to:
- visually inspect whether there is anything obvious causing the short, blow some compressed air into the sockets, see if that works
- desolder one side of all the sockets connected to that GI line, so that I can measure connectivity across them, and see which socket is the culprit/shorted and needs to be replaced
Now before I start desoldering... Am I missing anything? Is there something else that I could be checking that could cause the string not working? Anything else I should check for first?
Thanks for reading, and thank you in advance for your help!
20201024_194436 (resized).jpg20201024_194511 (resized).jpg