Macbook A1278 - 820-3115-B no chime, no display

[johnbeton]

Hello,

Currently I'm working on a Macbook A1278 with 820-3115-B board.
This notebook had some liquid damage between U7400 and U4900.

At first the laptop had no green light, and didn't power on, after cleaning the liquid damage, I replaced R7402 ad R7403 because they where out of spec.

Now the green light comes on, as soon as the charger is connected the fan start spinning, after 10 seconds it starts spinning harder.

USB light goes on. But still nog chime or display.

I checked voltages up untill ALL_SYS_PWRGD, seems good.

Could this be bad SMC ? I don't have an other SMC to test.

[mon2]

Re: Macbook A1278 - 820-3115-B no chime, no display

Perform a SMC reset using your keyboard.

https://discussions.apple.com/thread/8642800

If you remove the battery or do not have a battery attached after this process, the SMC needs to be reset again.

[johnbeton]

Re: Macbook A1278 - 820-3115-B no chime, no display

I tried the SMC reset, but it didn't help.
I notice now that the area under the SMC on the other side of the board gets hot quite fast, I'm going to dissasemble again and check if something is short there.

[johnbeton]

Re: Macbook A1278 - 820-3115-B no chime, no display

FIXED - Managed to get a SMC and replaced it, unit works perfect again