Macbook A1466 No power

[dclass-pro]

Hi guys, I have this A1466 macbook that doesn't start, the fan doesn't turn and it doesn't absorb anything, or rather... it absorbs 0.03A then every 5/6 seconds it absorbs about 130mA and then 0.. the 5V generates it only for an instant .
If I connect the power supply from bango the magsafe comes on with orange color (without battery connected),
PP3V42_G3H = 3v42
PM_BATLOW_L =3.31V
PPBUS_G3H = 8.59V
PM_SLP_S5_L = 0V and increases every 4/5Sec but only for an instant

I also tried to change the SMC but the result is the same... do you have any ideas?

[mon2]

Re: Macbook A1466 No power

On the coil that generates the 5v spike, measure the resistance to ground (with no power on the logic board).

There may be a shorted cap on that rail.

[dclass-pro]

Re: Macbook A1466 No power

no short circuit there are about 1.2Kohm

[mon2]

Re: Macbook A1466 No power

Remove all power -> meter in resistance mode -> measure the resistance to ground of

PPBUS_G3H

[dclass-pro]

Re: Macbook A1466 No power

have 6Mohm

[dellxps15]

Re: Macbook A1466 No power

board code 820-00165 ?
volt on L7560

volt on L7430.... spie to 5 volt once ? twice? never ?

how many omh on R7320 (black on ground red on R7320 200 omh scale.

good cpu is around 026. lower then 016 can become dead cpu shortly.

[dclass-pro]

Re: Macbook A1466 No power

volt su L7560 = 3,3V
volt su L7430.... spie a 5 volt in loop

R7320= 20ohm

[dellxps15]

Re: Macbook A1466 No power

L7430 how many times spike ? 1, 2 or more then 2 ?
more then 2 check u6100 bios volts.

cpu heated up with hot air ? if so bad action. (never heat cpu or smc)
edit: if spike 1-2 times report volt of u8180

edit2: if 2017 cpu can get low as 15.6 omh.

[dclass-pro]

Re: Macbook A1466 No power

on L7430 more than 2 times
on u6100 on pin 8 i have 3,3V

I have never warmed up the CPU, I have changed the SMC with a new one but nothing has changed
on u8180 i have a very fast peak of 2/3V

[dellxps15]

Re: Macbook A1466 No power

u8180 peak on wich pins ? pin 5 should be 3,3 stable.

[dclass-pro]

Re: Macbook A1466 No power

yes on pin 5 have 3v3v and pin 1 have peak

[dellxps15]

Re: Macbook A1466 No power

diode mode on pin 1 of u8180 ?
pin 1,2,4 should be 1320 in diode, while pin 5 is 450. pin 3 is gnd.

[dclass-pro]

Re: Macbook A1466 No power

in diode mode with red lead to ground and black lead to pin:
1=544
4=344
5=450
i have a motherboard here the same and i have the same values

[dellxps15]

Re: Macbook A1466 No power

check value R1462. check R8178 volts pin 1-2.

check also r1460 r1461

[dclass-pro]

Re: Macbook A1466 No power

R1462=100k
R8178 = 100ohm and in volts I have the peak of about 2/3v fast every 4 sec
R1460=100K
R1461=100K

[dellxps15]

Re: Macbook A1466 No power

volt on r8177 pin 1 ? check if stable or oscillate.

[dclass-pro]

Re: Macbook A1466 No power

oscillate

[dellxps15]

Re: Macbook A1466 No power

check diode mode on that resistor pin. then page 13 of schematic check all left volt of incoming pins like: PM_SYSRST_L, PM_PCH_SYS_PWROK, PM_PCH_PWROK and so on. check if stable volts.

[dclass-pro]

Re: Macbook A1466 No power

r8177 in diode mode to gnd have 464
PM_SYSRST_L oscillate
PM_PCH_SYS_PWROK oscillate
PM_PCH_PWROK oscillate
PM_PWRBTN_L 3,42 fixed
SMC_ADAPTER_EN 3,42 fixed
PM_BATLOW_L 3.31V fixed

[mon2]

Re: Macbook A1466 No power

Review this thread and update us with your progress:

https://boards.rossmanngroup.com/thr...an-spin.58148/