[SOLVED]820-00165 no fan spin but has magsafe

[nik1981]

Hi all, I have another 820-00165 with no fan spin after liquid damage. Traces of liquid near SMC, U7701 and U3210.

Ultrasonic cleaned, jump wire from C3286 pin 1 to pin 18 of U3210 as the test point between them had nearly vanished.

U7701 removed and replaced as it looked bad and I couldn't guarantee there wasn't crap under it.

SMC had a bit of a reflow to see if it changed anything.

PPBUS_G3H = 8.59v
PP5V_S5 = 5.04v
PP3v3_S5 = 3.33v
PM_SLP_S4_L = 0v
SMC_PM_G2_EN = 3.42v

Any ideas before I remove the SMC to take a look under there?

 

[JohnB8812]

This could be anything. PPVRTC_G3H present? Upload picture of BIOS area, U1950 area, and hopefully you removed JTAG.

 

[nik1981]

No Title

Yeah, PPVRTC_G3H is 3.33v at C1910. Excuse the photo, I had to take a picture of the screen with my phone..lol

 

[nik1981]

Jtag is off.. although it was mint

 

[nik1981]

This is a 2017 Mac, purchased 6 weeks ago. Wine spilt on the table and some splashed in the rear vent apparently.

 

[JohnB8812]

Yeah that looks clean . PM_DSW_PWRGD present? Also PP3v3_SUS present on the board and at U6100?

 

[aprendiz]

Voltage on R1300 to R1303 both pins??..

 

[nik1981]

for PM_DSW_PWRGD I get 0v on R1451 pin 1.
for PP3v3_SUS I get 0v on C1204 and U6100.

R1300 pin1 = 3.33v - pin2 = 3.33v
R1301 pin1 = 3.33v - pin2 = 2.99v
R1302 pin1 = 3.33v - pin2 = 3.21v
R1303 pin1 = 3.33v - pin2 = 3.32v

 

[JohnB8812]

Ok PP3v3_SUS missing and PM_DSW_PWRGD missing is no good. Resistance to ground on PP3v3_SUS? Missing DSW PWRGD means either corrosion under the SMC or bad SMC.

 

[nik1981]

124.7k from C1204 to ground

 

[JohnB8812]

So my guess is 3v3_SUS is missing because the SMC is either bad or has junk under it.

 

[nik1981]

And off it comes

Thanks for the help so far

 

[nik1981]

I reballed the SMC. I now get 3.33v on PP3v3_SUS and PM_DSW_PWRGD is 3.42v.

Still no fan spin though

 

[JohnB8812]

Voltage on PPBUS? Any pulsing on PM_SLP_S4_L?

 

[nik1981]

PPBUS is exactly 8.6v - PM_SLP_S4_L jumps to 3.3v about 3 seconds after connecting the charger but doesnt do it again until you unplug and plug back in

 

[JohnB8812]

Hmm. Does CPU VCore do the same thing?

 

[nik1981]

PPVCC_S0_CPU is jumping to 3.3v also, it does it twice. The other may do it twice also but I might have missed the first one.

 

[JohnB8812]

3.3 volts on CPU VCore....???? If that's the case, this is likely fucked.

 

[nik1981]

Yeah just double checked and they both jump to 3.3v twice and then quit

 

[nik1981]

I'm checking at L7320 pin 2.. Is that correct?