Magsafe LEDs, what is normal?

Discussion in 'MacBook' started by mathog, Dec 24, 2010.

  1. mathog macrumors newbie

    Dec 24, 2010
    When the magsafe power connector is plugged into my daughter's Macbook the LEDs on the connector do not always light up. However, lit or not, the computer sees the adapter because the status shown on the power indicator icon changes from "Power Source: Battery" to "Power source: Power Adapter". Is this normal, or should there always be LEDs lit when the magsafe connector is attached? For what it's worth, she says her roommate's adapter behaved exactly the same when plugged into this Macbook.

    There are some small cracks around the power connector on the Macbook, and the magsafe connector tends to tilt down. She say it has not been dropped, but it could have been bashed in that corner while in her backpack. I tried propping it up with a bit of eraser so that it was square to the machine, and it didn't make any difference.

    The Macbook identifies itself as model "MacBook6,1", with an Intel Core 2 Duo at 2.26 Ghz.

  2. EricNau Moderator emeritus


    Apr 27, 2005
    San Francisco, CA
    That is not normal, I'm afraid. The MagSafe's LED should be either green or orange when connected to the computer (assuming it's also connected to a power source, naturally).

    How old is this computer? Is it still under warranty?
  3. SandboxGeneral Moderator


    Staff Member

    Sep 8, 2010
    Orbiting a G-type Main Sequence Star
    The LED is supposed to always work. But it sounds like it burned out or like you said got smashed and broke. As long as it's still doing its job of charging, it should be fine.

    If it's still under warranty or Apple Care, you may be able to get a replacement.
  4. mathog thread starter macrumors newbie

    Dec 24, 2010
    It is still under warranty, but since there are a few cracks around the power adapter, they can probably point at that and try to wiggle out of it.

    I ran the laptop down to 85% and then plugged the charger in. It was orange for a while and then the LED went out. Even so, the laptop is still charging up. Looking at the pin diagram my guess is that small center connector (charge control pin) is not making good contact. If I had to place a wager I would bet that the LED color is set by the voltage the laptop applies to that pin, like +something for green and -something for amber, with the two LEDs in parallel and in opposite directions. Obviously if no connection there the LEDs won't light, but since Ground and V+ are present the laptop sees the adapter and says so at the battery icon.

    How much of an angle downward is the external connector supposed to tilt? I'm thinking that either the center pin is dirty or sticks, or that the slightly cracked case is letting the connector tilt down too far, and the center pin, being shortest, is the first to disconnect. Since two different adapters both behave this way, the latter is I guess a bit more likely.
  5. EricNau Moderator emeritus


    Apr 27, 2005
    San Francisco, CA
    That sounds like a fairly reasonable theory to me. The external connector (if I understand your question) is supposed to be horizontal - not tilted in either direction - and perpendicular to the computer.

    It never hurts to ask a Genius. Even if they decline at first, ask if you could connect it to a different power adaptor for a few minutes, to see if the issue is reproducible with other adaptors. If it is, then your hypothesis is likely correct, however, it's also possible that your adaptor is just faulty.
  6. eman macrumors 6502a

    Nov 5, 2007
    In the great white north
    On rare occasions, I have seen macbook charging lights go out after a small amount of time, even though the macbook was still charging just fine from the magsafe. I figured it was just a faulty charger and never had it fixed. When I used a different charger, the lights worked correctly.
  7. mathog thread starter macrumors newbie

    Dec 24, 2010
    What keeps it that way? Is the opening in the case plastic supposed to be so tight around the connector that it can only go in horizontally, or is the magnet alone responsible for the alignment? Now I'm beginning to wonder if the magnet inside might not be tilted, causing the connector on the outside to tilt too. That would explain why two different power adapters both do this.

  8. EricNau Moderator emeritus


    Apr 27, 2005
    San Francisco, CA
    Which style magsafe do you have? The original, or the new metal connector that connects at a right-angle?

    I noticed that the original was rather snug, such that the plastic could (theoretically) keep it straight; the new right-angle connector is smaller, so I think the magnet must keep it in place (I actually suspect this is the case for either connector.
  9. mathog thread starter macrumors newbie

    Dec 24, 2010
    It is the newer one where the cord runs parallel to the side of the laptop. There seems to be a lot of space around that connector, between it and the case.

    My daughter discovered that she can keep the charger's green LED lit by looping its cable up and over the top of the open laptop. Apparently that positions the charger connector in exactly the right geometry.

    We will take it in to an authorized Apple repair shop next week.
  10. mathog thread starter macrumors newbie

    Dec 24, 2010
    What size or the 8 screws on the back of the Powerbook??? Or rather, what size screwdriver is needed to fit it properly? #0, something metric?

    Well that was very nearly a complete waste of time.

    The first authorized repair shop looked at it and said, "look, the case is cracked. We will replace that for $130. No point sending it to Apple under warranty because this is clearly caused by the user." They tried an older model adapter and it worked (probably because the plug part extended a bit farther out of the housing than the new model, see below.) Sigh. My daughter swears she didn't drop it, but it might have banged something in her backback. There is a crack in the case at the power connector, but it is tiny, running from one corner of the power connector opening to the junction of the case clam shell, and the size and shape of the opening are not affected.

    How do I know? Well, we next went to an Apple store, waited a long time for the preposterously named "Genius" to have a look. While waiting to receive his words of wisdom I had the opportunity to look very closely at some other Powerbooks and the difference was obvious. While the power adapter hole was the same size and shape, on my daughter's the side of the power adapter hits the case, on the ones in the store there is about .5 mm of clearance. So the symptoms are consistent with the guts of the machine having shifted >.5 mm away from that edge of the machine, so that the adapter won't seat properly. The crack in the case is a red herring, I believe, since it runs nowhere near where the power adapter touches the case, and the case in that area is not otherwise distorted. Actually I wonder if the crack is not a result of the inwardly offset power socket, which would have resulted in the magsafe connector pushing very hard on a piece of the case which is not normally under any load.

    Those words of wisdom we waited for? The Genius pronounced that they could could fix it, but it would be a $450 dollar repair. Mind you, this is on a machine that works perfectly except for the power adapter not staying put.

    Anyway, since obtaining warranty coverage is clearly going to be a PITA we brought it back home, and I tried to take the back off to see what was going on inside. (I spend a lot of time fixing computers, but prefer not to open a machine under warranty if it can be repaired that way.) I have a fairly comprehensive set of screw drivers at home, including #1 and #00 Phillips, but none of them fit the 8 small shallow "Phillips head" screws on the back properly. Not wanting to mangle those screws, I will have to take it to work and open it up there, where I have a full set of driver bits. It would help to know ahead of time which size is the right one. If nothing is obviously shifted or broken I may just grind .25 mm of plastic off around the power connector so that the adapter will seat.

    On a possibly related point, is it normally difficult to release ethernet cables from their sockets on these models? We noticed from when we first unpacked this machine that while it is easy to insert an ethernet cable, it is a bit tricky to remove it again, since the "hood" on the cable presses against the side of the machine. As if, you guessed it, the socket was slightly offset inward in the same way as the power adapter connector.

    At this point I think that there is a fair chance, once the beast is open, to resolve the issue by loosening the internal mounting screws, shifting the motherboard towards the power connector, and tightening them all back up. At least, that might be true if there is some slop in the mounting holes, which is fairly common in circuit boards (but shouldn't be when connectors cannot tolerate .6mm offsets of said circuit board).

  11. mathog thread starter macrumors newbie

    Dec 24, 2010
    Which turned out to be close but not quite the problem. The motherboard itself was not shifted, and is in fact held in a particular alignment by pins that come up from the top case through it (one of which can be seen clearly in the after picture). The DC daughterboard on the laptop is held onto the bottom of the motherboard by two T6 bolts. Basically I started with the instructions here:

    but skipped most of it. The tools needed are as described on that page but you need a good #00 or #000 screwdriver. I used a Wiha Phillips #000 which worked beautifully, whereas the generic #00 I had tried before did not fit well. Quality tool for the win.

    These were the steps used to repair this laptop:

    1. Open the back of the case.
    2. Pop off the battery connector.
    3. Remove the rear vent (it sits over the LCD cable and it wasn't clear that that cable could be disconnected if the vent was still in place). This was also the hardest part because one of the Phillips screws was really in tight and the only way to get the vent free was to remove everything else, then wiggle the vent a little back and forth which loosened up that screw.
    4. Detach the LCD cable.
    5. Loosen the two T6 bolts holding the DC daughterboard on the bottom of the motherboard.
    6. Attach the magsafe cable, at which point the internal magnet on the daughterboard pulled on the cable and let me move the daughterboard outward slightly.
    7. 5->1 to reassemble.

    In the before picture (sorry, a little blurry) you can see that the external adapter is flush up against the case, this prevents it from seating properly. The two T6 bolts are indicated in yellow and the crack which supposedly caused all of this is indicated in magenta. In the after picture you can see that the adapter now clears the case (and it seats solidly to the internal DC board, so that the LEDs light). You can also see from the change in the uncolored area near the screw how a tiny shift in the position of the daughterboard is enough to relieve this condition. Notice how the edge of the crack is just at the end of the external adapter. Maybe something hit it, driving the board in and cracking the case, or maybe the DC board was never in the right position and the force of the adapter on the case cracked it there. Hard to say because while the adapter LEDs may not have been lighting regularly, it was working fine to charge the battery, so we would not have noticed this condition when new.

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