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Multi Boyz Litigator
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Multi Boyz
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Picked up a cheap but dead TMNT off of FB a few days ago and it showed up this morning.

Missing a few components but seemingly nothing irreplaceable. If anyone knows the value of C20, or can tell me what the 24-pin device at G8 is supposed to be, I would appreciate it!

There's also a gouge under F9 that took out a couple traces. If anyone can shoot me a high-ish res pic of that area on the underside I would really appreciate it!

Once G8 is replaced I'll start poking into it further :)

Edit: G8 is MCM2018AN45 (thanks @DecepticonZero)
 
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If it’s the first tmnt C20 is a 16v 1000uf
It is.

Thanks!

Ordered the sprite RAM. Will poke at the traces underneath later and see if it'll boot beyond what I'm getting now:

102957515_272486683869821_3086149754901181393_n.jpg
 
Initial pass I'd not noticed that the very large 051550 was missing. Ordered one from @caius and am waiting for it to show up.

Still waiting on the sprite RAM. Informeddelivery claims next week.
 
Would borrowing a TMNT PCB help you fix yours? I can mail you one.
 
Would borrowing a TMNT PCB help you fix yours? I can mail you one.
I appreciate the offer, but I simply don't know at this point if it would help.

Once the 051550 and sprite ram come in I will have a better idea of what I'm looking at, I think. For all I know those may fix it!

I may have to hit you up later on this offer if it comes to it though. Thank you so much for offering!
 
Sprite RAM came in.

Got impatient so I stole an 051550 off of another Konami board to get to work!

And now instead of a solid white screen it reboots entirely every second to the same white screen. Ha.


So now that we're in watchdog:

The Reset line on the 68000 is going high/low as expected.
A few posts have said to check the clock pin. It reads high and /occasionally/ flickers off of high. But I don't rightly know what that means.
 
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Was reading on some other repair log to replace the 6264 RAM if watchdog was going crazy.

Piggybacked some known good RAM on it and no change.

So a bunch of other threads say to start checking the 74LS chips, but how do I know what each pin /should/ be doing?
 
You kinda have to compare the inputs vs output pins of the chip based on what the chip does from the datasheet. You won't know for sure if data going into the inputs is correct, but can try to verify based on those inputs that the outputs are as expected. It can be difficult/impossible to do this on some of the tri-state or bi-directional 74LS chips though. Usually if I suspect one is bad I will pull it and test it in my programmer.
 
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