Backplane Board Problem - tried "Reflow" almost fixed need help!

Hello Guys,

GhostMik here again with some new "experiments"..

I got a used Mac Pro 4,1 Early 2009, the seller had advice me about "power problems"

but since the price was really good I have decide to go ahead and try to fix it.

At a first attempt the Mac Pro was boot but after few minutes it shut down suddenly.

I have try again to turn it on but nothing happen.

Then I have disassemble every parts, cleaned, put a new coin battery on the backplane and try again to turn it on, same behaviour, at first it boot then after few minutes it shut down without any action by me.

Ok, I have thought could be the power supply, but first I have checked the apple service manual and verified the DIAG LED. As stated in the manual the amber light was ok and the behave of the leds doesn't indicate a power failure but I have another Mac Pro 4,1 Early 2009 to use for testing and have exchanged his power supplys and the results was that the behave was the same. Checked twice the power supply in both Pros.

So, the problem was not the power supply but elsewhere..

Then I have tried to exchange the Processors Tray, neither this has work.

After all this attempts I have point at the backplane board!

Inspecting it I have noticed some kind of spray was used on it and the board results sticky. Probably the ex owner already try to fix it sending the Pro to a "technician" that doesn't have done a good job.

Understanding that the problem reside in a failure in the backplane board I have try to clean the board with Isopropyl alcohol and then used a heat gun for try to "reflow" everything on the board since I still don't have found a schematics of the board and also I'm not a professional technician.

IT WORKS!!!!!!!!!!

After the "reflowing" I have put back the backplane board and try to turn it on....

Sbam! It works from 3 days right now :DDDDDDDD

I'm writing from it in this moment.

I have used it a lot in these 3 days, shut it down, then turn it on again. Wifi work, bluetooth work, all usb and firewire ports working but.....


If I try to put the Mac in sleep state it seems to work and the power light start to behave like normal but when i try to wake up it the power light start to blink 3 times like it behave when a bad ram was inserted. I have try different ram configuration and also the other processor tray I have for understand and the results are that the problem is not the ram but still the BACKPLANE BOARD.

For double check i have try the processor board and the ram in the other Mac Pro 4,1 I have and there them work flawless..

So my "reflow" has worked partially!

Could anyone help me pointing which part of the backplane board need to be checked to understand if is possible to fix it 100%?

As I have explained, except the sleep function the Pro is now working very very good!

Thanks in advance for any help..

이 질문에 답하세요 저도 같은 문제를 겪고 있습니다

좋은 질문 입니까?

점수 0


Did you get this sorted and is the board still working or has it failed again?


의견 추가하세요