Search results

No water damage, no obvious drops, tried two batteries, one of which is known-good. Any ideas where to start? ASD EFI shows no errors except the usual when the battery is low(sensor vb0r) which I know is normal. Can't see any fried chips or anything. R7120(pp dcin in rush etc,) voltage steadily...

Boot from external hdd macOS and see if internal ssd is showing up on DU. Or try internet recovery and see if it shows up in DU there

I've got one in great condition if you'd still like one, and are located in the US. Edit: whoops I didn't see this was a post brought back from two months ago

I have a 3662 with a bad U4801 and need to find a replacement. After I tried one from a 2012 3115 and didn't work, I was informed by duke that the IC has firmware on it. I found a link to some on Aliexpress...

Did you perhaps plug in/disconnect the tpad while the battery was plugged in? I just had another a1502 come in with no tpad/kb after the last person tried hotswapping the tpad connector. I also have the issue on a 3662 where I may have plugged in the tpad while the macs battery was connected...

I only have some 2936 which have nearly the same circuit. the pins on the 2936 have much more .635v on more pins I wonder if the 3662 needs part of the keyboard backlight for the keyboard and trackpad to work. It stopped working when I was doing tests on the keyboard backlight :/ Or maybe I...

Any luck? I'm still having the similar issue that you have after changing the u4801 ic again, i also checked the resistors around pch

Could a bad bios cause no power/fan spin?

I finally found something significant, q7030 appears to be welded to the board, trying to remove it tomorrow. I haven't been able to find any shorts either. Probably another time-wasting board. Might just use it as a donor seeing that most of it is in good condition.

I just tried replacing the smc from an identical model and same result. Also, thoroughly went through the board a few times to verify no other components are missing. I wish I knew what the other person did with the board. It didn't look like itd been worked on due to the typical dust I see on...

I'm measuring the connector on the board in diode mode with black lead on the pins and red lead on ground, is that not the correct way? Or should I reverse polarity?

Trackpad connector diode readings 1-2 = ground= 0v 3-10 = OL 11 = .65v 12-16 = OL 17 = .643v 18 = .456v 19 = .643v 20-21 = OL 22 = .36v I'm getting steady 3.3v on U 4801, which should make sense since keyboard power button and SMC reset work. So as long as the diode mode readings appear ok...

Noted, thank you for your help, I will put this board aside to mess with while I have spare time.

Whoops, I got distracted trying to learn to read hz in the oscilloscope, which I did manage. I see 3.29v on each of c1802/3

I actually have a multimeter with hz and it does indeed read 32.77k hz. I wish I knew how to check on my oscilliscope, but mine is a dinosaur. Analog from early 90s I believe.

Everything seems to be soldered in place correctly. The weird thing is I used the keyboard and trackpad perfectly for a month until I started poking around the Keyboard backlight circuit, I clearly messed something up. Maybe i was in resistance mode or something at some point. Keyboard backlight...

I'm getting 4.9v on pin 3(P5VS3_EN_L of q7852(SSM3K15FV), but not pin 1(No _L; 15ohm resistance to ground which seems short), which schematics show they should both be on. I tested and see the low resistance is on the PM_SLP_S4_L side. I forgot to mention U7940 has been replaced before, the...

SMC did have quite a bit of corrosion on the test points surrounding it, I would not be surprised. I will check those two circuits when I get back to my workshop. Thanks Duke for your help

Great, I will go over every pad/connection. Will trackpad work with keyboard disconnected?

This is my IC holder I use, the smallest it fits is an SMC, anything smaller won't hold: https://www.aliexpress.com/item/80-80mm-Stencils-Template-holder-jig-HT-80-silver-BGA-reballing-station/32776759559.html?spm=2114.13010708.0.0.8Mazmt and i'm not sure which RAM style the mac has but it...