820-00165 ALL POWER RAILS, BUT NO CPU ACTIVITY.

Yalnif

Member
No magsafe light at all. Tried known good dc-in boards, no light on any. Put dc board on other known good logic boards, and THEY get light. Just this logic board has problem written all over it I think.
 

Yalnif

Member
Got magsafe light again now. Just pulling my hair out, so going back to the start and seeing what is what.

It is the power cxycling thyat is bothering me. Obviousloy not right. Wht is making it do this??

Power on, run for a few seconds then shuts down and restarts itself. Every single time. Somthing in thye sequence is wrong....
 

2informaticos

Administrator
Staff member
Inspect J9500 for corrosion; especially pins 19 & 21.

Still restarts if LIO flex is diconnected?
No Magsafe light is normal in this case.
 

Yalnif

Member
Yes, already inspected J9500. No corrosion whatsoever.

Obviously you will get no light if the cable is diconnected. I know that. Board still starts, shuts down, restarts. Same.
 

Yalnif

Member
I think I need to work thorugh the start sequence step by step. At some point it decides to restart. THAT is the bit where things are not right. The fact it does restart is wroing as you say. But it is odd that it restarts just the once then runs at 620ma. Before the restart it is around 350ma.
 
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Yalnif

Member
You mentioned earlier in this thread that BIOS files are availeble here to download. Can you point me to where they are please as I cannot find them.
 

2informaticos

Administrator
Staff member
Don't read only your posts.
We have a lot of threads with usefull information.
Read ANY new thread daily and take notes when you find something intersting.

 

Yalnif

Member
Did I say something out of line or to offend you? Early in this thread you mentioned that BIOS files are available to download from this forum. I cannot find them. Someone else in another thread said the same thing, so not just me. I simply asked you POLITELY if you could point me to where they might be. You chose to repond with an odd reaction. Please tell me what you think I said wrong?
 

2informaticos

Administrator
Staff member
Wrong understood, I hope I didn't offend you.
I only want to make you understand the forum is full of usefull information.
And you can gain time if take notes and save all you think is important.

The above mentioned thread, I post two dumps recently.
Was strange when you've said didn't find them.
For me, looks very normal to read all the threads, at least recent ones.
 

Yalnif

Member
No problem. I think we had crossed wires, which is ironic for a forum that deals with electronic problems.

I am very grateful for all your input.
 

Yalnif

Member
Yes, I read your post again and it seems I misread it. My apologies.

I have read other posts and have now downloaded your two Bios dumps, thanks.

I am however no nearer solving this other than that the magsafe light is working again. The board however, will stay at around 559ma all day after doing its strange restart. This is the part I do not understand as it is not meant to restart at all.
 

2informaticos

Administrator
Staff member
You can try reballing, or changing SMC; get it from donor board, same model.

You can have broken trace, or something else damaged because of corrosion; after heat applied.
 

Yalnif

Member
I agree. Oddly, that was my train of thought yesterday also. I have a conundrum though, Should I reball this one, or take a big gamble on an identical SMC (same board exactly) from a donor that had severe liquid damage. I think I will reball this one as I know at least this one DID work. I will update later today.
 

Yalnif

Member
I finally worked it out. It is a broken board! In the scrap pile and I can get on with my life. There comes a point at which you can end up just wasting hours on a board. This is that board.

I am graetfeul for your help and I very much note that it was ONLY you that offered any help.
 
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