Print

[cod4fan]

Ok I bought two used xplorer guitar hero 2 controllers off of ebay but the thing is they turned out to be returns from a store, so i need some help fixing them. One one the blue button doesn't work and other its the green.

I know its not the little black pads, because i took it apart and physically touched the pads to the points of the circuit board.

So can anyone please help me fix them

[SlickWilly440]

How about taking one of the working fret components from one of the guitars and then replacing it with the broken fret in the other guitar.  That way you will have at least one of them working without any problems.

[RDC]

Look for a cold solder joint where the ribbon cable is soldered onto the fret board as well as the main board. If it's not that, then it's something on the main board and probably isn't going to be fixed. I had one of those awhile back to work on with a dead fret button and traced it back to the U4 IC on the main board, nothing could be done about repairing it since that IC is covered in epoxy and can't be replaced, but other versions of the boards have a different IC there that can be, just depends. Make sure the contacts on the fret board aren't covered in anything that would cause it to be insulated from the black pad of the button, make sure there's no dirt, grease or corrosion on the ones not working.

[SlickWilly440]

^
Yes you would have to resolder it.

[cod4fan]

ok i resoldered the wires but i didnt work so i tested the wires with a volt meter and cable 123 don't get power but 45678 do. so that means theyre is a problem with the chip, do u know anything i can do

[SlickWilly440]

I guess there is nothing you can really do then.  I searched google on how to remove epoxy and the responses claim next to impossible to removed the epoxy without damaging the component/board themselves.

Why not just return them and get a refund?  Or was it one of those "As Is" auctions with No returns?

[RDC]

Measuring it in that fashion isn't reliable in determining the cause, unless you measured a known working Guitar as well and notice some difference between them there.

[RDC]

QUOTE(cod4fan @ Nov 15 2007, 11:59 PM)

the auction was as is and about your epxoy problem it doesnt use epoxy instead there is hot glue which we easily removed

The hot glue is on the cable connections, and no one said it was hard to remove. The epoxy is over some of the U4 ICs on some versions of the board, other versions have a different IC at U4 that can be removed, but in either case neither has hot glue on it, if yours is different post pics.

[RDC]

It's not a matter of them getting power or not, it doesn't work that way. See that black thing that looks like it was glue just poured onto the board? It also has U4 written right next to it, that's the IC in question and you're not getting to it without ruining it, not on that board anyway and even on the other style board you'd have to have another one to replace it with, so unless it's something simple then they're pretty much only good for parts. Did you check the solder joints at the fret board? or just the ones there on the main board?

[SlickWilly440]

RDC, why do the IC chips need to be covered by epoxy?

[RDC]

QUOTE(cod4fan @ Nov 16 2007, 09:17 AM)

i resoldered the joints at both points the fret board and the main board

and so your telling me that the only thing to do is replace the u4 ic?

You can not replace that IC because of the way it's installed on the board, so unless something is wrong with the wiring or button contacts then ya may as well stick a fork in those things. About the only other thing that it may be are the Diodes there, D6, D1, D12, D10 or D9, but I seriously doubt any of them are bad. If the wiring, button contacts, Diodes and traces are all good, then the problem is either U4 or U2 and even if ya could replace them you'd need access to good ones, which ya aren't going to find anywhere but in a working Guitar.

I just removed the epoxy from one, ruined it in the process too, and the traces go right to U2, not U4 (epoxy was covering that bit of info up) but ya still end up in the same boat with needing a replacement and only being able to get one from another known working Guitar.

QUOTE(SlickWilly440 @ Nov 16 2007, 10:16 AM)

RDC, why do the IC chips need to be covered by epoxy?

They're all encased in some form or another for protection. In most cases it's a plastic package that has the leads attached so each connection is easily accessible for soldering, like the other ICs there. Those particular ICs are covered in epoxy because it's way cheaper and it's just mounted right to the board. The main large IC there on the insides of it are really no bigger than the one covered in the epoxy, it just ends up being that big because of the number of connections it has and the leads it takes for all of them.

[cod4fan]

I was reading on how to remove epoxy and it says to either use sodium hyroxide or pinesol, tell me if u think theyll work

[RDC]

1. You can not replace U4, even if you did manage to get the epoxy off of it.

2. I've already removed the epoxy and seen that the traces go to U2 now, not U4 as I previously had thought, so that's where the problem would be, and again you can't replace that one either unless you have another one.

[cod4fan]

thanks for your help, but im just gonna get a friend who fixes them to look at it