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texem

macrumors member
Original poster
Aug 18, 2010
68
7
Hi everyone,

unfortunately my cheese grater suffers from dead USB 2 ports (front and rear).
I checked everything twice (NVRAM etc etc etc ) and finally removed the mainboard to see if there are any burned SMD fuses . Externally powered USB devices are not recognized, only Bluetooth is ok (internally connected via USB). There seems to be another problem and I am lost without a circuit diagram. Any chance getting it ?

Cheers
 
:(:( searched for circuit diagrams but found nothing MP 4.1/5.1
 
according to block diagram of mp5.1, usb datalines leads to southbridge directly. this is bga-chip, and needs to be replaced. of cource there're some protection circuits of usb ports. check blown ic's on io-panel or near io-connector on the main board.
 
At least you can disconnect front board and jump start the logic board with the pads on it.

Then check the back usb ports, with luck front board pulls something down.
 
i once tried to plug my headphones in to my USB slot (front), a window pooped up saying something about over power protection and my USB ports all disabled (i panicked thinking id killed them all).

i think it fixed itself after a restart, so that may not be of help. (now i look when i plug in headphones :oops:)

do you know if you did anything to make the USB stop working? how long have you had the problem?

found the service manual if it helps
http://tim.id.au/laptops/apple/macpro/macpro_mid2010.pdf
 
thanks all for reply and for the link to the service manual, found it earlier but unfortunately it did not help here. Need a circuit diagram. I removed the front panel and started the Mac with the pads, still dead on rear USB :-(
Strange about Bluetooth is working and this module is connected internally via USB , so , possibly the southbridge is alive.
Anyway, w/o a circuit diagram of the motherboard it's hard to locate the problem.
 
thanks all for reply and for the link to the service manual, found it earlier but unfortunately it did not help here. Need a circuit diagram. I removed the front panel and started the Mac with the pads, still dead on rear USB :-(
Strange about Bluetooth is working and this module is connected internally via USB , so , possibly the southbridge is alive.
Anyway, w/o a circuit diagram of the motherboard it's hard to locate the problem.
There isn't a public/leaked/3rd party circuit diagram available for any of the Mac Pros. When someone is developing something Mac Pro related, the only possibility is to find a iMac/MacBook/Air/Pro 3rd party or leaked circuit diagram and try to adapt to the Mac Pro backplane.
 
sry, but there's no board schematics for mac pros. they are just very rare units for repair and yes, they are stable like the war machines. currently i'm waiting for the liquid damaged thrashcan for repair and have no clue where to find circuit diagrams for it.
there're several usb-hubs integrated in AF82801JIB chip. bluetooth module connected to separate hub, while others may be dead due to power fail or usb dataline fails.
 
I gave up trying to repair the Mac and just powered it up after 2 or 3 weeks again. Surprisingly the USB ports returned to life . Huhhh .. what's that ? I am happy about, but on the other hand what happened here ?
 
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The exact thing happened to me after an intern charged his phone with a usb a to usb c cable via one of the ports in the front. Apparently the phone drew too much power and the ports remained dead until I reset SMC.. don’t know why it didn’t help in your case though.
 
what happened here ?
Who can really know? Over the years, I've known several systems that self-resurrect after a few days. But in this case clearly a very cold reboot seems to have done it. QQ: have you ever replaced the small battery on the logic board?
 
I gave up trying to repair the Mac and just powered it up after 2 or 3 weeks again. Surprisingly the USB ports returned to life . Huhhh .. what's that ? I am happy about, but on the other hand what happened here ?
Self reparable USB fuses?
 
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