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Repairing Gemlight 386 motherboard.

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First post, by gmc

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I've got a 386UMC motherboard I'm trying to repair which has a few corroded tracks due to battery leak. I've spent a few hours cleaning the corrosion and repairing tracks/via's but still not getting any life out of it.

https://theretroweb.com/motherboards/s/gemlight-gmb-386umc

I've got a POST analyser card which is giving no codes / no BEEPs

Before I take out the oscilloscope should I at least get some codes with no VGA card, no RAM and no cache installed? Trying to start with the minimal hardware in case RAM/VGA is also faulty.

I've checked the supply rails and they are all good. No shorts to ground. 386 CPU is getting warm - not hot.
Also checked the jumpers are set correctly. Have also read the EPROM and it's good.
Reset is also working.

I found the full schematics and PCB layout here, so this will be a big help in verifying tracks/via's

https://gitlab.com/computerguy096/dtk-386-replica

Reply 1 of 2, by Horun

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Post a picture of the damaged areas please.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 2, by gmc

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I've repaired a few tracks on the back side, mostly from corroded via's.

Beep tested all the tracks/via's in the area and now all good.

The EPPROM area is still looking a bit green but continuity is good.
Also tested from all the pins on the CPU

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