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nate8organic

nate8organic

New member
Got in a liquid damaged 3462.
trackpad connector cable had corrosion and looked like pp5v_s4_cumulus was eroded away on the cable. next to smbus_smc so i suppose it had affected that line too. Did ASD and its showing th1H SMC IO failed.

Checked U5550 and its good.

Resistance on R5550, R5551 and R5552 is also good. R5550 seems to bounce around a lot but compared with another board and it seems to match up can you confirm that?

any ideas? should i be looking into the smbus_smc line?
When it powers on fan is normal and then at about a quarter way through the osx boot up fans slowly turn to full.
 
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dukefawks

Administrator
If Th1h fails with IO error there must be more sensors failing, do ASD again. Crap under U5550 or SMC is likely.
 
nate8organic

nate8organic

New member
Ran asd 4 times now, With only the IO error. no th1h. tried replacing smc but i only had one donor board on hand and it seemed to be no good, so i put back on the old one for now. going to order some in.
 
nate8organic

nate8organic

New member
yeah i set it to continue, first few times i tried to do it and it was running so slow i couldn't make it to continue before the drop bar closed. My customer is willing to wait so i bought some more donors. and will test the smc when they arrive and post back unless you suspect it could be something else.?
 
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dukefawks

Administrator
It's not the SMC. Either U5550 or one of the sensing transistors connected to it. So no donor needed as these parts are common on most boards.
 
nate8organic

nate8organic

New member
I replaced u5550, R 5251 5250 5550 5552 5551 and C 2411 5552 5551 5550 and Q5501 and still high fan speed.. what have i missed?
 
nate8organic

nate8organic

New member
i wasn't paying attention this morning and pulled u7300 and plugged the charger in and realized i messed up so i put it back on and then pulled u5550 and now i have no video. would pulling u7300 and plugging it in affect my video? also from the sounds of the fans after pulling the u5550 the fans seem to go full speed at the same rate as before. as soon as i can get my video back i will perform the asd.
 
nate8organic

nate8organic

New member
yeah no chime, i figured the same thing when i was looking into u7300. i tried a pram reset also and now the only one fan spins on and off. cant seem to get it back to spinning up anymore, should doing a pram reset make it stuck in this loop?
I guess this is probably for the better because iv spent to much time on this one.
Thanks for dropping in Louis! I should have know i fucked the ram when i did that :eek:
 
smiba

smiba

New member
Voltage of PPDDR_S3_REG? The chip is probably just dead or not properly soldered back on. The system will happily try to go into S0 without this voltage being there as its not being checked as existing (afaik)

Unless you kept solder bridges on the board I do not think this can break the board.... The behaviour without this chip would be that the mosfet simply does not switch and thus not create any voltage.
 
Last edited:
nate8organic

nate8organic

New member
smiba said:
Voltage of PPDDR_S3_REG? The chip is probably just dead or not properly soldered back on. The system will happily try to go into S0 without this voltage being there as its not being checked as existing (afaik)

Unless you kept solder bridges on the board I do not think this can break the board.... The behaviour without this chip would be that the mosfet simply does not switch and thus not create any voltage.
Click to expand...

smiba You were totally right bro! resoldered both u7300 and u5550 and everythings back to the way it was before. good looking out man. now will post back with new asd after i pull u5550 again.
 
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dukefawks

Administrator
TS0P would suggest you don't have the trackpad connected....Was this issue already fixed and you just did not have the trackpad connected?
 
nate8organic

nate8organic

New member
actually i think your right duke, because the trackpad cable is messed up and this is for a local shop who is going to swap that on there own so i didn't bother to mess with it, normally i would have replaced it. I will throw u5550 back on and send it out and have the shop see if the issue is gone when they connect a new cable. i wonder now if it was just the trackpad from the gecko XD
Will update after i confirm the issue with the customer
Thanks for the help duke
 
nate8organic

nate8organic

New member
now im getting TH1H sensor is reading above the high limit. could this be from u5550 not seated fully maybe? i did it in rush but it looked okay, but i haven't gotten this sensor error until now.
 
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