Model A1181 / 1.83, 2, 2.1, 2.13, 2.16, 2.2, or 2.4 GHz Core 2 Duo processor

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MacBook not charging, bad MagSafe board?

Seems to be a little more common issue on these older MacBooks, but I am unable to get mine to charge. Was working just fine, then just stopped charging one day. LED doesn't come on on the adapter (have an L-tip), and the screen says it's not charging. Don't think the logic board is bad, as the computer is running fine otherwise. Switched out the MagSafe DC in board, and still nothing. I have a new DC-in board on the way currently, as I am unsure if the one I switched in was bad. My second possibility, is that the charger I am using provides to much voltage. It is an 85W supply, and although that should theoretically work, as it was before, who knows... I checked the voltages at the pins on this board, and they measured as follows (from top to bottom, starting with black):

Pin 1 (first black wire): 2.90 V

Pin 2: 0 V (ground)

Pin 3: 0 V (ground)

Pin 4 (inner grey wire): 18.63 V

Pin 5 (outer grey wire): 18.63 V

So it has a DC supply coming into the board, but is not charging. Battery is good, and logic board seems ok. Any ideas? Thanks in advance!

Answered! View the answer I have this problem too

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First the current Mag-Safe power adapters offer the same voltages. It's just the amount of current they offer is different (Wattage).

Think of it this way your table lamp has the ability to have a 35 watt, 45 watt or 60 watt bulb. The AC powering the lamp is the same but the brightness of the light is different depending on the bulb you put in.

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Right, got that down(am studying electrical engineering). According to the specs for the charger it should be delivering 16.5 volts, not 18.63 though. My question is more what would cause the charger to not have the LED turn on or charge? The board is clean and has been tested, and the battery is good as well. If the logic board was bad, what would it be on there that would stop the led "return signal" from being correct?

Thanks in advance!

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Sorry Nick please don't take it wrong many people just don't understand Ohms law here (in this case P=I*E).

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Haha, no I gotcha. I agree, or know what a "load" actually is...

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The power supplies are interchangeable… your battery could be at fault. Look in System Profiler (or information) Power… the number of cycles on the battery and its "condition" can affect charging. A normal battery can last anywhere up to 5 years… depending on use/abuse it might be considerably shorter.

Check the contact points on the magsafe for crud or gunk - dirt tends to build up in the recesses.

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Nick - You'll need to get ahold of the schematics for your system to diagnose this down.

I suspect one or more of the switching FET's or the power switching IC has a problem. One of the big killers on these systems is static electricity when people put the hands on the exposed Mag-Safe contacts without properly discharging them selves.

You'll find them here in this picture: power switching. Look to the left of the large square capacitors near the heat sink. There you will find four 5 pin SMD chips these are the power FET's and near them is the switching control U7900 (ISL6257HRZ).

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Yep! This is exactly what was wrong. Pulled out the board and found the switching control unit had blown up...bummer! Don't really know how it could do that, but it's shot. New logic board looks like... Thanks for the heads up though!

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The part is available, how does the logic board look are the solder pads OK? If they are, this is not to difficult a job to re-solder a new chip down. Besides a double E cadet like your self could use the practice ;-}

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The board isn't in bad shape, just a burnt out component. Yeah, actually found a replacement board laying around from a friend, so probably just gonna throw that in. Always fun to heat up the solder gun though:)

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Nels Tate will be eternally grateful.
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