Soldering a Fan Cable to a MacBook Pro Logic Board

I’m embarrassed to admit that only a few months after spilling seltzer inside of my MacBook Pro, I have spilled yet another liquid. This time it was about an ounce of coffee instead of about twelve ounces of fizzy water. However, the saving grace was that I take my coffee black and without sugar, and usually black coffee spills are rarely devastating.

Reconnecting the Fan

As I did last time, I took apart the computer, removed the memory DIMMS, and disconnected the battery. I was very concerned about any coffee residue inside of the machine, so I attempted to remove the logic board. IFixIt.com has a guide on replacing the logic board. One of the first steps in removing the logic board is to disconnect and remove the fan. As I did so, I broke the connector between the fan and the logic board. Egads! And the small piece of the connector fell on to the kitchen floor, never to be seen again. At that point, I gave up removing the logic board and simply set the computer, keyboard facing down, on a dry towel to let it dry as much as possible.

A day later, I reconnected the battery and, with the back cover still off, I powered-on the computer. It was working! There was a brief moment where the letter G didn’t work, but after another day, the G would return to working order.

The good news was that my computer was working, but the bad news was that fan was not spinning. The fan is crucial to the computer’s operation: after only a few minutes of being powered on, the logic board was very hot. I immediately powered the computer down to prevent damaging my computer’s internals. Feeling defeated, I put the computer back on the desk and went on with my day. My biggest concern was that I would need a new logic board.

After fretting about my dear computer, I spoke with a friend of mine who works as a mechanic. His do-it-yourself attitude was a great help. He suggested rigging a piece of copper wire to bridge the broken connection. The fan has four wires that connect to the logic board. I’m unsure what each does, but he guessed that two of the wires were for DC power, one was a ground, and the other was for a temperature sensor or the like.

His solution worked. I was able to harvest a thin strand of copper from an RJ-45 cable. I inserted the strand into the fan connector and pressed the other end of the copper against logic board, where the broken connector was. I powered-on the computer, and it worked. The fan spun and was cooling the logic board. The only issue was that when I stopped applying pressure to the copper against the logic board, the fan would turn off. I would somehow need to adhere the copper to the logic board.

The obvious, albeit somewhat scary, solution would be to solder the copper to the logic board.

After reading up on soldering, I bought a very basic 40-watt soldering pen from Radio Shack. Along with a spool of the thinnest 60-40 solder I could find, I spent under $20. This was against most advice I read online about needing to get a soldering iron that has an analog (or even a digital) temperature control. If I didn’t need my computer this week, I would have opted to buy a better soldering iron and wait to have it shipped to me1. But time was crucial and thus the $20 gamble to reconnect the broken fan cable seemed worthwhile.

As you can see in the video, I don’t have the steadiest of hands when soldering, but the solder was good enough to get the connection working. The fan works at both the normal speed (2,000 rpm) and that really noisy speed (6,000 rpm) when I am processing video.

Reconnecting the Fan

The DIY attitude saved the day yet again.


  1. The two soldering irons I was considering were: iFixit Basic Soldering Station and the Weller WLC100 40-Watt Soldering Station

Leave a Comment

21 Comments

  1. i truly believe that the design is made to have these items break off when manipulated in any way !

    good for apple and bad for the client …

  2. Hi Juan,

    Thanks for sharing your story. Can you offer any advice for my situation? Like you I also broke off my fan connector (doh) though my mistake was made while removing the fan for cleaning. My local mac shop said I need a new logic board which of course will cost a packet. When I snapped off my connector I also managed to pull two wires from the connector (double doh). I presume I can just take a 50:50 chance with this when pushing both back in (or just order a new fan so the cables are correctly assigned?). I am sure that could be trouble.

    My main question though is what you mean by, ”I then inserted the other end of the copper wire into the connector.” If you look at my picture here (http://tinyurl.com/qjefphm) do you mean attach the far left wire that protrudes from the connector? The plastic connector has 4 wires and I thought each attached to the logic board via the plastic holder (see the row of 4 logic board ‘dots’ below and slightly to the right in my pic).

    So you just made one connection to the logic board with your extra wire? And your fan is back to normal (i.e changes speed, goes off when not needed etc)?

    I am not at all an experienced solderer but always think with a little application a lot can be possible and I might give your method a try. My laptop is at a general laptop repair shop at the moment. They are suggesting the equivalent (here in Sweden) of about 150 dollars for soldering each of the 4 wires to the logic board (or routing the power from somewhere else in the laptop). What do you think?

    Many thanks, Dennis

      1. Thanks for the suggestion. Immediately after this happened, I wondered whether I could just buy a new fan and cable, but the connection lead that broke was soldered to the logic board. It couldn’t be easily replaced without desoldering it from the logic board and soldering a new one.

        In the end, I soldered a piece of wire to where the broken lead was on the logic board and then ran the free end to the fan’s connecting cable.

  3. Hi Juan,

    Did you use any Flux to help with the solder? I’ve attempted to solder mine and it does work but occasionally disconnects so I think I need to revisit. I have no experience with soldering but Flux seems to help get the solder to where you want it.

    Thanks,
    Matthew

    1. @Matthew: I did not use flux. The iron did not touch the copper wire. I just basically tapped the solder and let it drip on the copper wire along the contact. I was lucky to get it right the first time. Here were are over a year, and it’s still holding.

  4. it is good if you have this by using a BGA rework station as this one is the best rework station for the reworking of PCB (Printed Circuit Board) I am sure if you do it you will get the best results as these machines are Full automatic BGA rework station that is special; you made for these types of reworking.

  5. Hi Juan,
    Thank you for the wonderful post. I the exact similar problem with my macbook pro 13. In my case I spilled orange juice and in the process of opening up the logic board I ended up snapping the wire that connects the cooling fan with the logic board. I bought a soldering iron and tried to solder the wire exactly like you did in your video. But then I managed to get two points soldered, although the solder was quite big compared to yours. I was hopeful that my fan would work in no time. Unfortunately it did not. I was devastated. I then again tried to resolder it properly but still no result. Now I am freaking out. Can you please suggest me how should I proceed further? Any help will be highly appreciated. Here are the two pictures and these are the two attempts I have made. And I am hoping for the worst now.

    1. It’s hard to tell what happened since the photos are a bit small, but if you soldered both wires together, it is shorting out the fan. You can try to desolder, but that’s quite difficult.

      1. Yes the wires were too thin and I think may be I must have soldered them all. So what do you think I should do now? Is it possible to repair it anyway?

  6. @Juan, it’s unclear from the picture exactly where you inserted the copper wire. There are four entry points and its my understanding that these wires cannot be bridged by a single connection or you risk nuking the motherboard. I’m actually shunning your technique in favor of soldering each wire individually. It is messier but at least I dont have to worry about the fan shorting out my board

    1. @Steven.

      You’re right! Bridging the wires together on the fan can cause big problems. That’s not what I did.

      I soldered the single copper wire strand on to leftmost contact point on the logic board without bridging any of the other connectors on the logic board. I then inserted the other end of the copper wire into the connector. Finally, I secured the fan cable connector back to logic board.

      In short, I simply jumped the connection between the leftmost end of the fan cable connector and the leftmost terminal on the logic board with the copper wire. That’s it. The trick is to get a soldering iron that is fine enough to make that single connection.

      Good luck.

    2. Just finished the job. Actual soldering took me about 5 minutes, which as a novice was quite surprising. I used some solder cream to isolate each of the connectors, then got in there with 0.5mm wire and a 1.5mm iron. A few light taps here and there and *presto*, success! So happy to be up and running again

        1. Thanks, saw your post since it is just identical to my situation.
          now i just temporaily attached my disconnected slot to the logic board with some .. super glue.. better get a smolering pen soon. thanks u are a life saver

  7. Juan, thank you for this article as it is very timely.I have a similar problem where I completely tore off the socket that the right speaker + subwoofer connector. I took your picture and circled which part that is here: http://oi48.tinypic.com/11gmzk9.jpg

    From the top you see a black rectangular pad, but beneath that is the connector with four wires attached to it, which connects to the socket which is supposed to be stuck to the logic/mother board.

    It actually looks almost identical to the fan connector with 4 wires and the socket that it plugs into.

    Okay, now that I clarified that, my problem is that when I was unplugging the “right speaker and subwoofer connector” from that socket, the damn socket came off of the motherboard. The socket is attached to the connector (that has 4 wires), and no damage appears to have been done to either the connector or the socket. The socket itself was originally connected to 4 metal points on the logic board from what I can tell. Here is a diagram I drew so you can better understand what I mean, apologies in advance for the retarded drawing, I was drawing on some shitty online paint program (OS X has no built in pant program unfortunately) with a trackpad + I suck at drawing.

    http://oi45.tinypic.com/if1r92.jpg

    From this picture, on the left is the socket, on there ight is the connector with 4 wires. Now the socket has these 4 vertical yellow “teeth” (on the underside of the socket that faces the motherboard, on the opposite side of where the connector would plug in)that attack to 4 metal “teeth” on the motherboard. They look kind of like these: http://oi48.tinypic.com/34yr4th.jpg which I circled in blue.

    My computer works fine but now I have no audio from the right side which totally sucks.

    After googling for a bit, it seems that others have came across this problem too as I guess these connections are really cheap and delicate (yay Apple!). In any case, how risky would it be to reattach the socket to the logic board? One person commented that he was able to fix it by doing the following:

    “used a standard solder iron with a brass spade tip. Steel seems to attract the solder so it sticks to the steel, which I didn’t want as I wasn’t going to add any solder to the board. With Brass the solder seems to stay in place.”

    Using the point of the spade, I applied the solder iron to each one of the four leads for about two to three seconds being careful not to melt the plastic.

    Without completely securing the bottom case, I turned the Mac back on and tested the speakers. They worked flawlessly. I finished securing the bottom case.”

    I have never soldered before in my life, though I do have decent hand eye coordination, but I have no idea what type of soldering gun (or iron), or type of solder to use. The other guy who I was unable to contact said he used a standard solder iron with a brass spade tip, but after googling for it, I could not find a “brass spade tip” anywhere. I read the ifix article you mentioned, and it said to “Touch the iron to the joint that you’re soldering, making sure to touch both the copper pad on the board as well as the lead on the part.” Stupid question but would the joint be the connection between the socket and the metal teeth on the logic board? So would I heat up the metal teeth on the mother board and also the yellow vertical teeth of the socket, and then release some solder onto both of them and that’s it?

    What do you recommend I do? Also, are there any good soldering irons and soldering materials and any other tools that may be useful that I can get off of amazon.com? I don’t have a radio shack near me. If you could recommend a unit that would do the best job for the type of repair I’m trying to do I would extremely grateful. From what I can tell, though, is that there are different sized soldering guns (or tips?), and I think I need a “fine-tipped” soldering tip/ironing gun or something just because the socket is so small.

    Also, if I spill solder on the mother board, will that destroy the entire thing or will I just screw up the audio connection (and any other type of connection nearby).

    If you can help me out I would be sincerely and extremely grateful.

    Thanks,
    Mark
    (If you contact me, could you send me an email with any tips and advice?)

    1. Re: Mark,

      ATTN: Juan

      Can either or both of you please respond to the question that Mark posted and that I will restate in my own words, here?

      While replacing a broken optical drive in a MacBook Pro mid 2012 I had the same thing happen but instead of the fan it was the connector (bottom half of the socket) that sits on the logic board and links up the subswolfer/right speaker cable (which are apparently combined). The socket into which the speaker cable goes is still attached but the bottom half of the socket, which sits directly on the logic board via four little strips (“teeth”), are severed (it looks to be a clean break).

      1 Q. Using a 12-watt solder iron and no additional wire or solder would it be possible to reattach?

      To recap what Mark said, the connection looks almost identical to the fan connection depicted in this blog post (four contact points laid out in tiny parallel strips).

      2 Q. If I use this as a guide would it be *right or *wrong to attach all four connection points to the bottom of the socket so that it is reattached to the board one for one OR if I am reading the comments further upstream am I to understand that connecting all of them may bridge a gap and short the connection and that, instead, only the leftmost “tooth” needs to be re-soldered back to the board?

      I know this is an old discussion but it’s still relevant, IMO, because Apple was selling the 2012 MacBook Pro essentially unchanged until last year so these are still out there in large quantity some four years after they were originally released.

      Nobody ever replied to Mark but Mark if you get this and can let me know how it turned out, please reply ASAP.

      And Juan, if you see this first can you clarify your understanding of whether it is a BAD idea or a GOOD idea to connect the socket (bottom half) back to the logic board using a one-to-one approach?

      Thank you.

      1. Hi Newsview,

        This post is really old so my memory of this repair work is pretty fuzzy. Yet this is also the most popular post on my blog so clearly there are a lot of people brave enough to try, and I hope that it has helped some intrepid Mac users.

        A1. I don’t think it’s possible to make the connection without some solder, but you might be able to do it without additional wire. As I wrote, one of the connecting “teeth” broke, fell to the ground, and was never seen again. That’s why I needed to improvise a new “tooth” with the wire. But unless you can get the connector to stay in place, you’re going to need solder.

        A2. It would be very wrong, in my estimation, to bridge all four connections. They’re separate for a reason. In the case of the fan, at least two carried power and bridging them would short circuit the connection. It would have some comparably ill effect on the right speaker/subwoofer cable.