820-3536-a not turning on, magsafe orange light

[Yoel Ren]

came in looking good, not turning on
ppbus_g3h : 12.58v
ppvrtc_g3h : keep cycling between 3.4 and 3.3v
pp5v_S5 : cycling
pp3v3_S5 : cycling
pm_slp_s5_l : cycling below 30mv, i will treat is as 0v then
is this tps problem ?

 

[2informaticos]

Original Magsafe 2 60/85W charger?

Try SMC bypass mode first.
Check U1900 area for corrosion.
Do you get steady 32KHz at pin 12?

 

[Yoel Ren]

yeah magsafe 2 85w
ok i will try smc bypass : not working
u1900 no corrosion, magsafe unplugged, but pin 12 not steady, cycling

 

[2informaticos]

Cycling DC level,or 32KHz oscillation is not constant?

"magsafe unplugged"
Why???
You need to make the board works on charger first.
Let the battery unplugged.

 

[Yoel Ren]

sorry I mean 32 khz oscillation is not constant at pin 12 of u1900
battery is unplugged

 

[2informaticos]

3V42 steady at pin 13?
If yes, change U1900.