820-3536 not turning on

iClub

Member
Good afternoon, this Mac came in for repair of the headset not working on one side, I fixed it by changing the U6201. In the final tests the mac stopped turning on, I checked that there was oxidation in the Q7630, I replaced it but with no result.
Sometimes it wouldn't give led in the MagSafe.
I removed the u6201 to eliminate the possibility of it being defective.

Voltage:


PPbus: It oscillates between 12,45V, 12,61 and 12,71V;
pp3v42 3,42V; PP3v3_Sus 0,8V oscillates; PCH_BatLow 3,34V; PLT_RESET_L 30mV;
 
Last edited:

2informaticos

Administrator
Staff member
You forgot 3V3_S5, which is very important.
If pulses, then check SMC_PM_G2_EN.
Also check diode mode to ground on all big coils.
 

iClub

Member
Voltage / diode mode

L7630 7mV, no pulse / 0.148
L7310/20 0V, no pulse / 0.068
L7430 163mV, no pulse / 0.134
L7520 1.370 ~ 1.261V, without pulse / 0.427
L7560 3.35V / 0.149
L7195 5,5V
L3095 0V, no pulse / 0,526V
L7130 12.45~12.61V

SMC_PM_G2_EN 3,42V
 

2informaticos

Administrator
Staff member
I said "can be", not "it is".
Need more checks to find the culprit.

If you reply the questions, we gain some time...
 

iClub

Member
PM_RSMRST_L 0,275V o pulse when SMC_ONOFF is triggered
PM_PWRBTN_L starts high at 3.42V when triggering the SMC_ONOFF drops 0.355V

Do not enter SMC Bypass mode
 

2informaticos

Administrator
Staff member
3V3_SUS must appear first, in order to get high PM_RSMRST_L.

Are you sure PM_SLP_SUS_L is missing?
PM_BATLOW_L is still high?
Check PM_DSW_PWRGD, SMC_ADAPTER_EN and PCH_DSWRMEN.
 

iClub

Member
PPVRTC_G3H 3.35v
PCH_CLK32K_RTCX1 0.360v
PCH_SRTCRST_L 3.34v
RTC_RESET_L 3.34v
PCH INTRUDER L 3.070V
PCH INTVRMEN L 3,25V
PCH_DSWVRMEN 3,25V
 
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