A1278 820-2533-B no wifi


I have an A1278 820-2533-B that had liquid contact and has no wifi. It has a burnt L3404, L3401, and some surroundig caps. I don't have any 820-2533-B to steal those parts. Can I use those parts from any other board?



I don't think i have a short in PP5V_WLAN. (OL in diode reading).

Just to be sure, i should jumper L3404 pin 1 to C3422 pin 1, correct?
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Tks. That's what I've done, I have 5V on PP5V_WLAN , but still no wifi. It says no hardware present.
I'm not sure if i had to have continuity from L3401 (pin1) PCIE_CLK100M_MINI_CONN_N to C3422 PP5V_WLAN, but i don't have it.
Can it be U3402 (I have 3.3V on PP3V3_S3)? How can i check it?
What should I check now. Can you help?
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Just realized that the wire that i've jumped has "exploded" / breaked after a few reboots.
It seams that i have a short on the airport. With the airport cable connected, i get 0.002 in diode readings, and 0.5 ohm to ground on PP5V_WLAN . Can i check anything else?
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I'm sorry. I've write the wrong model. It is an 1286 820-2533-B model.
The cable goes right to the interior of the display. Is there a card inside?
Tks. Didn't know that.
The cable was presured by a screw. After disassembling it, the short has gone.
Now I have 5V on PP5V_WLAN and 0.504 in diode mode, and 50kohm to ground, but no wifi yet.