MKIII ultimate CMOS U49 chip error help

jcar302

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Well, i managed to install (right or wrong remains to be seen) MK ultimate in my MKII cab.
Swapped over an entire control panel and box that someone else had already drilled a hole in so i didn't have to molest my original.
Both run buttons work. Some buttons didn't show continuity when depressed and didn't work, so i swapped out the micro switches with some off the orignal board and are good now.

But when starting up i get the cmos u49 chip error.
Says can't restore factory settings.

Now the machine appears to play fine, i think the issue is memory.
None of the stores i had time to stop at today had the exact battery, but i tried the one that came on the board and the one from the MKII board.
I tested both and used the one that was better and had 2.9xx volts, which i figure should be plenty.
No change.

The u49 chip is soldered.

Here are my install pics, i have messed with dip switches as suggested in other posts during my million internet searches, but doesn't seem to change anything.

Also note that the bottom white connector i didn't connect anything to, the connect on the existing harness has at least one less pin and i figured better safe than sorry.

My biggest concern is that the volume doesn't stay where i set it, basically it runs full tilt. As soon as i press a button to select the lowest volume (which it does fine) at the next screen it reverts right back.
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I left the sister board in from MKII, but it's not hooked to anything.

If you need more details or pics, just ask.
This is the first game i've ever been inside of and it's a learning experience.
If it helps, MKII ran fine.

Thanks,
Joe
 
u49 is one of those lil ram chips below the battery there in your first pic. 2.9v on the battery should be enough tho they're rated at 3.2v

you won't find br2325's you'll have to go with CR2325's instead.

everything looks wired fine to me. i'd check the traces to the battery and to u49, sounds like maybe there's a scratch cutting both lines?? snap a good pic of the back where the battery and u49 solder joints are for us if u can.
 
u49 is one of those lil ram chips below the battery there in your first pic. 2.9v on the battery should be enough tho they're rated at 3.2v

you won't find br2325's you'll have to go with CR2325's instead.

everything looks wired fine to me. i'd check the traces to the battery and to u49, sounds like maybe there's a scratch cutting both lines?? snap a good pic of the back where the battery and u49 solder joints are for us if u can.

Ok will do, when I get some time friday.
Thanks,
joe
 
If the CMOS chip is registering as bad/red, then it's not a battery issue. Even if you remove the battery completely, the U49 chip should still read green/good. I would try pressing down on the chip itself to check for loose pads under the chip. I have a couple boards right now that have graphics issues unless you press down on the chip. The U49 CMOS chip is directly next to the battery.
 
Thanks zeno, I have located already.
When the system does its initial check where it go through the boxes, the u49 box lights up green.
After that is over it says sound 1.xx sound or something like that.
Then on the next screen it gives the error in a sentence up top saying its bad.
Not sure if that matters.
 
Thanks zeno, I have located already.
When the system does its initial check where it go through the boxes, the u49 box lights up green.
After that is over it says sound 1.xx sound or something like that.
Then on the next screen it gives the error in a sentence up top saying its bad.
Not sure if that matters.

Oh, well then if a new battery doesn't fix it (I would recommend getting a new one when you can for the full voltage - MK boards are extremely picky about voltage) then I would do like the other guys have said, turn the board over and check for broken/scraped traces and bent socket feet that might be touching each other.
 
Ok, installed new battery (yes it did read 3.2 like you guys said), still does the same thing. u49 error
For the most part the volume is the biggest issue, you can only take so much of it on full blast in the house.

Took some pics of the board, but i didn't see anything and i used a magnifying glass, so i'd suspect you guys don't see much, but here goes.
The two big solders near the center are the battery, so the u49 chip is slightly down and to the right. edit: probably should of skipped the magnifying glass, pics are better, lol.
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So if we can't sort this out, where do i go from here?
I guess options are:
Buy another for $100
Send it to get fixed? If so, where?
Buy mkIII and take the chips out of this one?
Will this one have any ebay value to someone that can fix it? (i'm always honesty on ebay, i would fully disclose the issue)
Try fixing it myself?

Thanks
Joe
 
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everything looks in order, except that 1 bent solder leg on that u54 (which prolly is doing nothing wrong. and there is a tiny lil spot by the left most solder point of the battery (tho could just be the picture).

So what i would do is (not that this will fix anything but it's worth a try): remove the battery and check to see that there is continuity from the solder leg in question to the end of that trace (just before the other solder leg of the battery) if there is then there's no issue with that trace. hit the component side of u49 with compressed/canned air (make sure there's no dustbunnies causing havok.

if those don't do anything here's the last few things you can try and cross your fingers:

Check the voltage at the board from the battery, best spot would be from the end of the 1 trace to the solder leg next to it (+ and -)

go over the solder side of the board and bend any legs like that bent one back straight. pull all the chips and clean the legs with super fine grit sand paper, clean the edge connector with a pencil eraser, pull and reseat all the plcc chips (u45/47/35/ect...)if you have a puller and feel confident. check the voltage at the chips with the game on (shoot for 5.10v).

you can also try resetting to factory defaults (why not it's worth a try).


not sure if any of that will help but that's just what i would do. Since it's the u49 causing all these issues i doubt any of this will help but as i said it's worth a try.
 
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Hey brood, trying most of what you suggested other than pulling the chips, don't have a puller.
No change.
When i goto factory defaults, it says specifically "failure in CMOS ram".
Made a few calls too, seems this is fairly common and repair will cost more than it's worth.

One more thing, not sure if it's the settings or not, when i play the computer pretty much always they finish me off (i lose alot) with friendship or babality, in fact i don't seen i've seen a fatality.
What's up with that?

Thanks for the help, i will put up a want ad for another.
Then sell this one on ebay (honestly of course i have perfect feedback an intend to keep it that way). I've watched a few ones go off with similar errors and for some unknown reason people pay 75% of the cost of a good one.
Guess they either want the UMK chips or they know how to fix these things.
 
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One more thing, not sure if it's the settings or not, when i play the computer pretty much always they finish me off (i lose alot) with friendship or babality, in fact i don't seen i've seen a fatality.
What's up with that?

check your dip switch settings vs the manual. other than that, i think it's just the machine being nice ;-)


pulling the brown socketed plcc chips mostlikely won't do you much good so don't worry about pulling them, the major thing is making sure the other chips are making good contact, and no pins on the solder side are bent over touching other traces. (tho i think if this was one of the problems it would cause issues with other components and show up in the boot up test).

you could always wire in another volume pot to your speakers and control the volume via that, tho this would require some mild wiring hacking.

The chips on that board are worth a good amount as they are expensive to begin with (as long as they have windows on them and aren't the once program kind) they can be reused.

nothing wrong with losing a lot we all did at one point, and how else are you suppose to learn?
 
nothing wrong with losing a lot we all did at one point, and how else are you suppose to learn?

I was always a winner. j/k

speaking as someone who had only played the game in an actual arcade maybe 2 times, and then spent many years playing the SNES version for a little while, and in MAME for about 8 years, it was tricky to adapt back to arcade controls. the combo system itself is kind of tricky to get the hang of if you're not very good at memorizing patterns. the run button's placement was difficult for me to get used to as well, over time though I guess I got my hand to stretch properly enough to run and do combos with ease.

I never bothered much with fatalities, they're extremely hard to do some of them in this game, and the rest that are doable, I never bothered trying to memorize them. very different when you're 11 and MK2 was hot and your mission in life was to remember every single move or finishing move and being a grown adult and having other things to deal with in life. lol

I find UMK3 a ton of fun to play though, I just like hammering out those button sequences and destroying people. :D

also, most likely it was Ed Boon that said it, their games have a difficulty curve where it'll let you win the first 2-3 fights easy, and then the AI ramps up and starts obliterating you.
 
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