[SOLVED] 820-3437 Liquid Damage

[arnonabuurs]

Hi, I have a Macbook Air 13 inch 820-3437 with some small liquid spil around Q8150. I have replaced this chip and fixed a trace to R8156 that was gone. The fan makes a tiny move but system doesnt boot. U6100 and U1950 have power and look clean but pin 5 is pulsing and no are other lines. After measuring all voltages I get following:

820-3437

PPBUS_G3H = 8.6
PP3V42_G3H = 3.44
PP5V_S5 = 5v
PP5V_S4 = pulsing 0-5v
PP3v3_S5 = 3.34
PP3v3_S4 = 3.34 pulsingPPVCC_S0_CPU = pulsingALL_SYS_PWRGD = pulsing
PM_S0_PGOOD on U1950 = pulsing

What should i be looking for?

 

[smiba]

Might be wrong but have you checked the bios resistors? Also check for continuity

 

[G.Beard]

Have you checked for shorts on other rails and the 6259 Isense resistors are in value?
Tried burning your lip on the board?

You got a short somewhere probably.

 

[dukefawks]

First thing you check is if CPU Vcore is also pulsing and we go from there.

 

[arnonabuurs]

Hi Guys, thanks for all the replies was busy with some other boards, but now back onto this one. Yes, CPU VCore is pulsing from 0 - 1.8 and back to 0.

 

[arnonabuurs]

I found a tiny liquid spil on R1380 and R1500 near Y1915 and after replacing this I got a spinning fan, thanks for the help and this ticket can close.