820-3437

iFix

New member
Hi guys.

i have this a1466 820-3437 with a wifi issue. there was some liquid damage that i've fixed because it couldn't read the SSD. I managed to install it with the wifi working at the moment but now it stopped. I've replaced u3550 and all voltages are going through it normally. When in OS trying to switch on the wifi it tries but not switching on. Any advice please?

Many thanks
 

2informaticos

Administrator
Staff member
"all voltages are going through it normally"
Depends what you consider normal; always better to post values.
 

2informaticos

Administrator
Staff member
Sorry, I was thinking about U3540; post its voltages.

BTW (for the future), use schematic when you reffer to component pins, not boardview.
 
Last edited:

iFix

New member
u3540
pin1 PP3V3_S5 - 3.3v
pin2 P3V3WLAN_VMON - 1.1v R3554 pin1 is 3.3v
pin3 AP_RESET_L - 3.1v
pin4 AP_RESET_CONN_R_L - 3.3v
pin5 GND
pin6 SMC_WIFI_PWR_EN - 3.4v
pin7 AP_CLKREQ_Q_L - 0v r3553 pin1 PP3V3_WLAN is 3.v
pin8 - 0v
pin9 GND

Replaced R1342 , r3555 , r3554 , r3553
 

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2informaticos

Administrator
Staff member
Why did you replace it?
All voltages are good.

Try another airport card, clean the connector.
Check PCIE_AP data/clock traces and components.
 
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