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Lightmeter Sekonic L-508: main logic board damaged from battery leak

ElectroDummy

New Member
Hello!

I would like to ask for your opinion regarding the repair of the Sekonic 508 light meter. It was damaged due to a leak from an AA battery, and there are traces of the leakage, especially on the main logic board. I don't have much experience with complex issue identification in repairs. It seems that even though the main contacts of the + and - from the AA battery are heavily damaged, I was able to measure voltage on other components (albeit randomly) and verify that it's possible to "trace" through the battery contacts further into the circuit using a multimeter.

However, after cleaning everything up with isopropyl alcohol and connecting the battery to the light meter, nothing seems to happen at first glance. Upon closer inspection, I discovered that when I press the power button, the display briefly flashes and shows some information. (attached photo from a video I have recorded) This is the main reason why I'm writing, as it gave me the impression that there might still be something salvageable.

Regards, Jan
 

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It may take a whole bottle of Isopropyl with a toothbrush and a pressurized air jet or vacuum to clean off the severely conductive alkaline spill. The contamination is hard to remove especially under IC's. The display LCD bias is high impedance voltages for contrast may be faulting from a charge pump voltage boost circuit leakage.
 
Corrosion LOOKS minimal on holder side of board but much worse on lcd side. My first step would be CLEAN and then check vias and traces near SW109 and ALL traces under LCD..to verify continuity. WATER DAMAGE also????
How long has unit been unused?
Be sure to apply enough voltage and current for startup?
Zebra strip under lcd display,, does probing or pushing anywhere cause a display.
 
I bought the exposure meter at a flea market for $10 just for fun, because I'm already looking for one, and I might as well buy a decent one. At the same time, I found it interesting to try to repair it. I cleaned it focusing on the worst parts. I will clean the board thoroughly and disconnect the LCD to take a look underneath. I'm thinking of lightly sanding any damaged connections with a small grinding machine and then soldering them to restore all lines, followed by covering them with solder mask. I've also read that vinegar has good decontamination effects, but I'm not sure if it's safe to use. Another thing that makes me a bit nervous is the contacts under the buttons, which are made of black conductive material. I have no experience with how careful I need to be when cleaning them and whether they can be replaced with something if I damage them.

Just out of curiosity. Would you give a chance to such a board? I don't want to waste time on something that seems like a lost case at first glance, and it's hard for me to estimate.
 

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