Repairing Game Boy Color

[Hex]

Hi guys, I've attached some pictures. I have a multimeter and it's reading the power coming from my battery pack but sort of ends right there, I can get it in places near to it but anywhere towards the bottom right of the circuit board there's nothing.
I can't turn it on and essentially it's useless right now. I bought the Game Boy (and others) to repair them. Can anyone give me some advice on where to test for power, or where to solder in order to get basic functionality, just the essential ground points?
I'm more than happy to put my multimeter in a specific spot and give you the reading in order to troubleshoot.
Feel free to add me on Skype, PM or Email me if you want a more direct conversation.
Skype: Falloutkidz
Email: [email protected]

 

[CocaCola]

What happened to that phono jack? Looks like someone cooked it with a torch...

As for what to test or not test, get a working unit and sketch out the circuit, or at least the ground plane and some positive rails for testing... Establish test points and then test against the dead units...

Besides that look for obvious blown parts or parts known to fail...

Also be gentle on the heat, it might just be toasty flux but where you soldered the battery wires (ground) to the board looks like it might have been a overheated, keep that up and you will start to lift pads and destroy the board...

 

[Hex]

What happened to that phono jack? Looks like someone cooked it with a torch...

As for what to test or not test, get a working unit and sketch out the circuit, or at least the ground plane and some positive rails for testing... Establish test points and then test against the dead units...

Besides that look for obvious blown parts or parts known to fail...

Also be gentle on the heat, it might just be toasty flux but where you soldered the battery wires (ground) to the board looks like it might have been a overheated, keep that up and you will start to lift pads and destroy the board...

I figured that the solder may have become brittle so I used a heat gun to try and "reflow it" seeing as the bottom right half of the board, in fact, not much of the board at all was receiving any power. I guess I may have left it too long around the headphone jack and melted some of the plastic.

Unfortunately I have no idea how to do that. I'll look up a tutorial on the internet, hopefully I'll figure it all out. I really hope that I can get it working.

 

[CocaCola]

I guess I may have left it too long around the headphone jack and melted some of the plastic.

And quite possibly caused other damage to that area, since you toasted it...

Also that is just the 'controller' sub assembly board with minimal function beyond detecting button presses and some output, there is A LOT more that can go wrong with the main board of the game system... And that main board is almost certainly where most faults will be...

 

[Hex]

And quite possibly caused other damage to that area, since you toasted it...

Also that is just the 'controller' sub assembly board with minimal function beyond detecting button presses and some output, there is A LOT more that can go wrong with the main board of the game system... And that main board is almost certainly where most faults will be...

It appears that the battery power isn't leaving it's little sockets that I soldered them to. Once I get power in the bottom half, I assume that the top half would also receive power.

 

[CocaCola]

It appears that the battery power isn't leaving it's little sockets that I soldered them to.

Based on what testing? Have you tested the multiple ground and VDD test points on the board? Have you tested for power before and after the power switch?

The schematics for this system are easily obtainable so testing is pretty straight forward...

 

[Hex]

Based on what testing? Have you tested the multiple ground and VDD test points on the board? Have you tested for power before and after the power switch?

The schematics for this system are easily obtainable so testing is pretty straight forward...

I've used a multimeter and it reads a '1' on the two battery sockets, but everything else has the same level regardless of whether the batteries are in or not.

Easily obtainable, or easy to make?
I'll try and find one now assuming you meant the first one.

 

[Hex]

Unfortunately I have no idea what this means. I've only just started researching circuitry, coming from a background of IT. So excuse my lack of knowledge.

 

[CocaCola]

That is one part of the schematic there are other sheets that all need to be combined to make the complete board...

If you can't read a schematic and based on what I have gathered you really need to get grounded in electronics before you tackle a project like this...

First thing might be getting a few tutorials on how to use the different functions of the multimeter... If it's set to continuity it will read 1 (aka infinite) when there is no continuity and a decimal percentage related to the Ohm scale when there is continuity... Other settings will read different things, and it's not uncommon for newbies to pop the internal fuse rendering it useless...