What did I just fry? How to troubleshoot a circuit?

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revans

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Ok so I made this 12v battery meter here: **broken link removed** I've got it on a vero board type thing. I absent mindedly put it on top of a 12v battery and evidently a couple solder joints touched the terminals as a green led flashed a couple times and now it doesn't work. How can I tell what part has screwed up? The last time I fried a circuit the broken part started smoking no such luck this time. I'm guessing the green led might have blown, but from my experience with the circuit it doesn't matter if one led is taken out of the equation, the rest should still go. I have a multimeter and so can measure voltages etc but I've never done anything like this before so have no idea where to start...Thanks for any help you guys can offer
 
There are a lot of parts which might have gone across the river "Jordan" after having gone through St. Elmo's fire.

Best advise: Rebuild the whole thing with new parts (if time is an issue).

If it's not, check each individual part for proper function before reuse. Take special care of all polarized elements like transistors and electrolytic caps.

Boncuk
 
As boncuk said build it again

your LM3914 is probably dead and all the other components are easy to check

for re use

Robert-Jan
 
If you were lucky, the 4007 might have blown, doubt it though, but easy enough to check with a DVM, check volts to the chip, if good then I would say bye bye to the chip.
 
For as simple as that circuit is, just build a new one. If you are relying on it to monitor an important battery, then why take chances?
 
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