820-00165 No S0, SYSCLK(s) trying to turn on, corrosion all over

G.Beard

New member
Machine was covered in coke.... The whole bottle I think.
Damaged areas were:
U6100, U1900, Q8150, U1950, U5000, U7100, U8300, J8300, U7090, J9500, Q7155, Q7706

Cleaned up all areas, and replaced all caps and resistors and ICs with corroded pins / pads that I could see, except the SMC (so far) as the outer balls look OK.

Voltages tested are:
PPBUS_G3H = 8.6
PP5V_S5 = 5V
PP3V3_S5 = 3V3
PP3V42 = 3V42
PP3V3RTC_G3H = 3V3

After randomly stabbing the wrong pin (pin 3) on U1900 (trying to test for PP3V3_S5 on pin 2), found that SYSCLK is blipping on / off.

Still very much in confusion and trying to figure out the order in which power rails turn on.

Where I should be looking first with this?
 

dukefawks

Administrator
First look at 5V_S4 at L7520, it is probably pulsing. Judging by your description this thing is a hell hole.....
 

G.Beard

New member
OK, so now have fan spin and only green light. CPU gets hot. Fan is not doing the start / stop like it should. I'll throw on the heat sink, stop burning my finger and test some voltages again.

I think there was an issue around U1950
 

larossmann

Administrator
Staff member
this may work after a 30 second 80 celsius cleaning in the UC. but it sounds like a fucked board with a bad CPU
 

G.Beard

New member
00165 does not start/stop, only 3437 and 3435.

Oh OK.
Since whenever I ask a question that requires a longer answer here, it's skipped, please would you provide a yes or no answer to this...

5V_S4 can only turn on with PM_SLP_S4 right?

And the signal for.....

What tells the PCH to turn on PM_SLP_S4?

Thank you
 

dukefawks

Administrator
There is no answer for that that does not require reading and understanding the 500+ page datasheet on the Intel PCH, but here you go:

http://www.intel.com/content/dam/ww...datasheets/7-series-chipset-pch-datasheet.pdf

Read that and you will understand why I cannot answer why your SLP_S4 is not there.
I did ask if it was pulsing, could pulse once or could cycle. Measure while plugging in power to not miss the one pulse. Use a scope as multimeter is too slow to catch a single pulse.
 

G.Beard

New member
There is no answer for that that does not require reading and understanding the 500+ page datasheet on the Intel PCH, but here you go:

http://www.intel.com/content/dam/www...-datasheet.pdf

Read that and you will understand why I cannot answer why your SLP_S4 is not there.
I did ask if it was pulsing, could pulse once or could cycle. Measure while plugging in power to not miss the one pulse. Use a scope as multimeter is too slow to catch a single pulse.

Thank you. Page 69 power management interface may also be useful.

5V_S4 is now working.
CPU turns on.
No chime.
MagSafe only has green light.
 

dukefawks

Administrator
Check CPU Core voltage and see if it drops in voltage after a second or if it comes on and off and on again.
 

G.Beard

New member
Also magsafe being only green looks like SMC issue, probably crap under it.


Thing is, when the boards was not powering on there was green / orange.
I have already replaced SMC this morning.
Checked PP3V42 getting to pull ups.
Checked pull up resistor values.

Check CPU Core voltage and see if it drops in voltage after a second or if it comes on and off and on again.

I will check shortly.

Thanks
 

dukefawks

Administrator
Well, this could be anything at this point. The usual suspects is the clock chip or corrosion on SPI ROM data lines. Besides that this is just a rabbit hole board.
 

G.Beard

New member
Yeah it was pretty fucked. I'll leave it here then and try SPI data lines and clock chip as both had corrosion.
Thank you for your help
 

G.Beard

New member
Audio is on the IO board, so probably bad connector/cable/IO board.

So I have tested 3 IO boards and cables. Bleeped out the board connector on J9500, checked all solder joints are OK.
Checked the enables are good for audio around U8040, even replaced U6410 and anything in it's path....

I feel like I have come too far with this board to give up because of audio!
I have pretty much rebuilt the entire board because there were little girl tears over this fucked MacBook which is why I did not just laugh and send it back.

Any more clues or are we at the end?

Thanks for your efforts
 
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