A1278 - 2351: No start

[HTR-Informatique]

Hello,
I have a MacBook Pro 13.3 "early 2010, A1278, EMC 2351, SN WQ031BPZATM, 820-2879.
He does not want to light up anymore because of the water spilled on the keyboard.
Green LED of the charger that turns on, but nothing, black screen, no noise, no fan.
No visual damage on the motherboard.
Nothing that heats up abnormally.
I suspect Q7030 and Q7035 but not sure, how to test them?
Cordially.

 

[2informaticos]

Disconnect keyboard and use R5014/15 pads, instead of power button.
Post exact PPBUS_G3H voltage; keep battery removed.
Also check L7750 voltage and RTC signals.

 

[HTR-Informatique]

I had already tried to boot the motherboard without the keyboard with R5014 / 15 but nothing.
For PPBUS-G3H, without the battery, the voltage fluctuates between 10 / 9V up to 3.3 / 2V.
For the RTC signal, how do I test it, I test the voltage of RTC_RST_L, RTC_CLK32KXTALIN, RTC_CLK32KXTALOUT and RTC_CLK32KXTALOUT_R?

 

[2informaticos]

You must first get correct and steady PPBUS_G3H voltage.
Remove F7040 and check voltage at L7030.
Post exact resistance between pins 17/18 and 27/28 of U7000.

 

[HTR-Informatique]

On L7750 I have 0V.
F7740 is OK, beep on both sides.
On L7030, without F7040, I also have a voltage that fluctuates between 4 and 2 V approximately.
No resistance between U7000 pins 17/18 and 27/28.

 

[2informaticos]

"No resistance between U7000 pins 17/18 and 27/28."
Are you sure???
Fix the problem; check schematic and replace corroded resistors.
Also check traces continuity.

 

[HTR-Informatique]

I have 0 ohm.
The tracks are OK, I send pictures of U7000.

 

[2informaticos]

"No resistance between U7000 pins 17/18 and 27/28
----------------------
I have 0 ohm"
Can you specify???
Please check schematic.

"The tracks are OK"
Did you check traces to R7020/21/22 and R7050/51/52?