Macbook pro A1706

[hani]

the fans spin and all the general voltage present but the
Voltages not present on:
L7430
L7410
L7420

the usb amp meter start from 20v , 0.23A then the amp goes to 0.01 then return back to 0.23
there is no picture and the capslock not light.
if i connect the battery the Amp goes to 2.9 A but the same with out pic

 

[2informaticos]

Can we know what 820-xxxx board you have???

 

[hani]

820-00239-09
L7430 to ground 3 ohm

 

[hani]

any help ??

 

[2informaticos]

L7410/20/30 have all the same value; and 3 ohms looks good enough.
There appears voltage only under hogh graphics load.

Any history available?
Did you check external video and USB activity?
PRAM reset tried?

BTW, L7210/20 have also very low value as normal; and you said to get voltage there.
Do you note any changes in that voltage in the first 10s?

 

[hani]

i try pram reset -nothing change
in first 10 sec nothing change 0 volt at l7210
usb amp meter start as normal 5 voltto 20 volt and amp from 0 to 0.23to 0.05to 0.01-0.23

 

[2informaticos]

In the first post, you've said missing voltage only at L7410/20/30.
No voltage at L7210/20 now???

 

[hani]

as i write before general voltage present but not on L7210-20
iam trying from morning to find solution ,but icant
i need help, i have 20 volt -0.30 A from usb c amp meter withou the battery
the fan spin both of them , i can use power swich to turn it on and off
but capslock without light
Voltages on
L8000 0.9 volt L8050 1volt L9660 1 volt L7900 1.1 Volt L9400 2volt LB700 0 volt L3500 0 volt L8410 0volt L7030 13,1 Volt L7660 3.3 volt L7600 5volt BKLT_EN_R 3.3 volt PPVOUT_S0_LCDBKLT 0volt

 

[2informaticos]

Try to post accurate information from the beginning.
You only said no voltage at iGPU coils, which is normal (in first post).
If you don't get VCORE (L7210/20), this prevent the board to start; CPU core is not powered.

Don't bother to measure image/backlight signals if CPU is not running.
Try to put some logic in the process repair.

"Any history available?"
Liquid signs, other usefull information???

You can try known good BIOS, just in case.