4-Slot Cross Hatch All of a Sudden

[trenog]

Hey so I've had my 4-slot work perfectly fine for the longest time, sometimes I wouldn't play it for a week or more, but I would power it on and game on it all the same with no issue.

Today I fire it up for some bday gaming and it immediately goes to a crosshatch. I tried removing all the games and selectively putting individual titles in each of the slots separately but nothing worked. I tried increasing the voltage when I found that it was below +5v this entire time (I measured +5v from the PSU but I guess it dropped under load) but that didn't work either.

I disassembled it and checked for a possible battery leak but there doesn't appear to be corrosion or acid underneath the bottom board or around the battery.

I am seriously stumped and really would appreciate some input into my problem

 

[shadowkn55]

There could still be corrosion underneath the battery that is still hidden. You'd probably have to verify connections before ruling out battery corrosion.

 

[trenog]

There could still be corrosion underneath the battery that is still hidden. You'd probably have to verify connections before ruling out battery corrosion.

Yeah I just checked and it's as I feared. The corrosion must have happened a long time ago because the battery itself doesn't look like it has created any acid for a while. There are several traces that are disconnected now that time has worked its way through the solder mask.

 

[Tyranix95]

Remove the battery legs.

Clean the corroded area/ battery site.

Then use your multi-meter--set it to the lowest ohms test--and check all the traces in the area.

If a trace is good, then it will have the same reading as if the tips of the probes were touching. If it's bad, then it will have no reading at all (cut trace) or a different reading (corroding trace).

Use kynar wrapping wire to repair bad traces. Neatly bridge the trace from point to point. Then re-test.

After all traces test ok. Then neatly arrange wrapping wire and use a dab of hot glue to hold it in place.

 

[shadowkn55]

use a entire stick of hot glue to hold it in place.

Fixed.

 

[Tyranix95]

Fixed.

---

Imagine if drakon used Nail Polish instead of hot glue.

 

[trenog]

Got it fixed! Only one of the traces connecting to CN10 on the right had broken down and so a single wire under the board later I'm back in business

Just gotta find a replacement to slot back onto the board so that it can keep its memory. Though it looks like channelmaniac has found a way http://www.neo-geo.com/forums/showthread.php?196121-MVS-Battery-Replacement-Guide

Also, big thanks to this thread for giving me the right traces to follow: http://www.neo-geo.com/forums/showthread.php?131636-4-slot-PCB-interconnections-pinout-%28a-contribution-to-the-crosshatch-problem%29