Galaxy S4 motherboard issues

[TonyStank]

Hello,
I'm trying to fix my friends I9505 that got its power button forced and partly broken off motherboard. Button can't be replaced because pcb pads are broken. Motherboard can be turned on by pressing volume down and plug in usb trick. That is ok for me but my friends really needs power button.
So i got another motherboard from smashed i9505, but it has weird issue. It shuts of after some time of use especially if under load, after that it can turn on shows galaxy s4 logo or sometimes andoid logo and shuts off and no sign of life for few hours.
I got two batteries B600BC and B600BE they work fine with first motherboard, so its probably not battery issue.
So i hope that someone can help me to fix one of these motherboards. For first maybe i can solder connector and for missing pads use kynar war and connect to alternative spots on motherboard if there are any.
For second maybe its overheating or something but its cpu temperature is top 37°C .

 

[Jfalls63]

Hello,
I'm trying to fix my friends I9505 that got its power button forced and partly broken off motherboard. Button can't be replaced because pcb pads are broken. Motherboard can be turned on by pressing volume down and plug in usb trick. That is ok for me but my friends really needs power button.
So i got another motherboard from smashed i9505, but it has weird issue. It shuts of after some time of use especially if under load, after that it can turn on shows galaxy s4 logo or sometimes andoid logo and shuts off and no sign of life for few hours.
I got two batteries B600BC and B600BE they work fine with first motherboard, so its probably not battery issue.
So i hope that someone can help me to fix one of these motherboards. For first maybe i can solder connector and for missing pads use kynar war and connect to alternative spots on motherboard if there are any.
For second maybe its overheating or something but its cpu temperature is top 37°C .

Have you tried to re-flash the stock firmware on the new motherboard? Could be a software issue.

 

[TonyStank]

Have you tried to re-flash the stock firmware on the new motherboard? Could be a software issue.

Yes I flashed it to stock 5.0.1 . At first it had rooted 5.0.1 then i flashed it to CM13 6.0.1 Nighly and was runing fine for 3 days then shut off issue started, and first thing i done was flashing it back to stock but still same issue.

 

[nu2andy]

Sounds like you need to get another logic board that is guaranteed to work. Was it pulled from a fully working phone? I've purchased and fitted 2 boards but were tested by the seller and guaranteed in working condition.