Mid 2010 Model A1278 / 2.4 or 2.66 GHz Core 2 Duo processor

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Help me identify capacitor/resistor

Hello guys I'm having issue with "No hardware installed" for WiFi... WiFi/Bluetooth/iSight cable and it's connector is OK,but I found out that one resistor/capacitor on the other side of logicboard (which is connected to one pin of WiFi connector) is burned...

There are screenshots of res/cap location

http://s13.postimg.org/stfwlequf/IMG_000...

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http://s7.postimg.org/758t1i057/IMG_0005...

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oldturkey03, thank you so much!

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I have a lot of smd circuit boards, how can I find that part instead of buying it? I mean how to measure it? Just ohm meter? Im a bit confused because I never heard of reference designator (not on my language)...

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A reference designator is nothing but a number on the logic board which corresponds with a part on a schematic. Apple does not show the reference designator on their logicboard. You will need an inductance meter or an oscilloscope to identify an unknown inductor.

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Just buy a dead board for thirty bucks and use that to scavenge everything you need.

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NeleRS, it is neither a capacitor nor a resistor ;-). That is reference designator L3404 which is a 120-OHM-1.5A inductor type Chip Ferrite Bead in a 0402 package. Available at places like this. Just remember that there must be reason why it blew up the way it did. Check for any short circuit and damage to the traces and other components.

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Also make sure the black tape is over the wifi connector pins so the shielding thingie doesn't short the pins out. That is how this inductor always blows.

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Is this schematics inductor value is correct?

The value is stated 90 ohm-100ma

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@salmonjapan I am confused by this. L3401? Why?

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@oldturkey03 , I had a mbp 13 with the same issues as NeleRS, just that to confirm if the value to use is 90 ohm-100ma or 120-OHM-1.5A ? thanks btw

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@salmonjapan NeleRS had an issue with L3404 which is a 120-OHM-1.5A . If you have an issue with L3401 than the value for that is 90 ohm 100ma

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This topic of mine was a long time ago... My MacBook is working great from the day I've done replacing few burned components... The thing I want to mention is that I've found a tiny piece of wire (size of the hair) under the "J3401 right clutch connector" legs, so to prevent this, @salmonjapan protect your connector pins on the motherboard with some tape over the legs, so nothing can get inside. My problem is that my laptop is sometimes on my small electronics workbench so there is always a lot of stuff that can short anything on the motherboard.

I just wanted you to pay attention on that connector which is usually (not always) a cause of these components burning around.

Good luck with that! ;) Thanks to @oldturkey03 for helping me with my problem!

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NeleRS will be eternally grateful.
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