820-2915-B: CPU fan always on high (and some other issue)

Antonio

New member
Customer came in with a 15 inch 2011 pro last week that he somehow ripped the fan connectors off of the board on. The GPU fan connector came off in a way that the pads were safe, so that one was a pretty simple process to solder back in place. The CPU fan on the other hand... Two of the pads were ripped off of the board. Pins 1 and 4 were taken to the shadow realm, never to be seen again, and having seen enough yugioh, I knew that the only way to fix this was finding another source for both of the pins. Thankfully pin 4 was ground, so that was easy enough to find another place to solder to. Pins 2/3 were hardwired to their pads, and I wound up scratching through the PCB right next to where pin 1 was ripped off and used that as the new 5v source (although I guess it's the exact same source considering it's the same trace that lead to that pad...)

Any way, that all went fine and everything was in place. Turned the computer on and nothing blew up or started on fire, but the CPU fan was constantly running at full speed. The GPU fan is perfectly fine. I'm not getting a kernel panic, and the CPU usage is still seemingly fine, so aside from it being a little annoying, no functionality is lost to my knowledge.

I ran the ASD test and it showed that the fan sensor was reading "low", and that there was an SMC I/O problem or something of that sort. I'm assuming whatever is supposed to read back from the fan is damaged past the 3rd pin (which i'm "pretty" sure is the one showing how fast it's going?)

So yeah, i'm pretty much stuck at this point.

Another weird thing is that the keyboard seems to be going in and out, and the trackpad completely doesn't work (besides click obviously). On the keyboard I can put caps lock on and i'll see the green light come up, then turn right off. If I hold it down, the light just blinks. It's unusable past that. No clue if that's related to this at all. I've cleaned the keyboard connector, and to my knowledge there hasn't been any spills on this computer. The power button works consistently, so i'm pretty sure the keyboard itself isn't damaged...

Any help would be greatly appreciated!
 

tlon19

New member
have you taken the board out of the machine yet? there might be water damage, seems like from your story that the customer was annoyed from the fan noise and tried to take matters into his own hands.
 

Antonio

New member
Yeah, i've taken the board out. Everything looks fine. He originally was trying to clean the heatsinks and stuff (which he's done by himself fine a few times before), and somehow ripped the connectors off this time. He's been in here before for something else and the CPU fan thing was fine at that time. He's a long time customer, so he knows that lying to us about the problem is just going to make it harder to fix even if it makes him sound stupid to tell us what he's done :p
 

larossmann

Administrator
Staff member
Do you have the boardview software for this board?

Do the following.

1) Click the pin of the fan connector that came off.
2) Read the signal it is called on the bottom of the boardview software.
3) Click "net" or "nets"
4) Enter the name of that signal.
5) See where else it shows up on the board.
6) Run a wire from that point to the pin.
 

Antonio

New member
There's only 3 points in that entire signal, all of which seem to be fine. I'm thinking maybe it's somewhere with pin 2 now, and that after it gets over near the SMC on the back side of the board is the problem. Gonna check that whole line of crap tomorrow. Thanks!
 

Antonio

New member
It doesn't look like there's even a place for it on the board like it was ripped off or anything. Are there different revisions of the same board that have different board view files? That one specific component is the only thing I can't see on this one, but it's like it never existed.
 

zockysworkshop

New member
Download and install SMC fan control app and gonna show you the CPU AND GPU temperature also you can regulate the fan speed.
 

Antonio

New member
There's no place for Q5660 to even go? Well, according to what the board view shows anyway...

Does this look correct..?

The dots there do look a bit odd, but not like it was ripped out, just like it was never there to begin with.
 

Antonio

New member
No Title

I'm stupid and tried to post a link to the picture in the last post because I didn't see the image upload button. Ignore the link in the last post ;(
 

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dukefawks

Administrator
Nope, but there are not that many SOT363 packages on the board. Just multimeter on beep and go probe around.
 

Sykulski

Member
On the other side of the board than you are looking right next to the fan connector. The board view file is also showing it on that side. It is an error in board view... Same component (Q5660) shows up on both sides of the board.
 

Antonio

New member
Odd. Either way, Q5660 seems to be going everywhere it should just fine, but continuity isn't everything I guess :/ I have another board from the same year (though it's a 17 inch), if I were to take Q5660 from that board and put it on this other one, would it function the same?
 

Antonio

New member
Okay, figured the problem out. Everything I was doing was right, but I just overlooked one tiny stupid thing. I didn't know that a square around something in the board view meant it was a component. I was actually missing R5665. The two pads under it were in such good condition that I thought it was just two empty places that were irrelevant, so I overlooked them. I kept testing for continuity between the pin right above it and the pad near the SMC. I checked the board thing again and saw I was up one point too high, tried the correct one and got continuity, which sucked because that connecting being broken was pretty much the only possible reason for it not working in my head at that point. After that I somehow wound up getting a burst of "slightly less stupid" and decided to check what that was going to and realized that literally the only problem was that R5665 was a component (that happened to be missing) and not just two unused pads... Took R5665 from another board, put it on and now it works just fine :[)

Now that the fan problem is out of the way, I still have the issue of the keyboard and trackpad. I'm getting absolutely no movement from the cursor, and the keyboard seems to be connecting and disconnecting at a set speed. I even went in to the settings thing and saw it coming in and out. I cleaned the contacts/connectors of both, but of course it didn't help. Any suggestions?
 
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