For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
Came in with little bit corrosion on the upper side. Fan turns on for 1 sec, then turns on again for about 15 sec then turns again and it does't stop but no post.
L7310/L7320 = 1,7V
Have tried another U6100 but all the same.
I looked wrong. It took 0.37A.
Just replaced BIOS from a donor board before I read your post. It shows the image of apple now. I don't have BIOS programmer. Have to order reprogrammed BIOS chip from Ebay.uk.
Thanks 2informaticos (y)
No sign of corrosion. 20V on both USB-C ports. 0,33-0,037A. Fan starts, but no chime, no activity on external USB or image on external display.
L7210/L7220 0,9V which seems ok to me. Where to start?
There is a pin burnt in lcd connector on lcd side and on connector cable. Replaced it and tried with test lcd but it's like it is not recognised. I'm thinking to lift U8510 and measure EDP_PANEL_PWR_EN. I can't se other ways to do it.
I have checked in diode mode first :)
It seems that replacing U7190 (P5V1) was the problem all the time. Now stable 5,1V at P5V1_CHGR_VDD and P5V1_CHGR_VDDP.
U7100 doesn't get hot and the battery is charging.
Thanks a lot for your help (y)
You had right. Pin 23 and 25 (CHGR_BOOT and CHGR_PHASE) are shorted (0ohm between) and R7121 and R7122 measures in kohm in stead of 20 ohm before. just replaced U7100 and after plugging power in measured 1,6V on CHGR_PHASE. Disconnected power and CHGR_BOOT and CHGR_PHASE again shorted.
Strange. Now voltage at F7140/41 is 4V. U7100 still gets hot.
Resistance between pins 17 and 18 is 3,8 ohm. Resistance between pins 27 and 28 is 22,8 ohm.
Came in with U7100 blown. Replaced it, Q7130, Q7135, Q7155 and R7105 (measured kohm instead of 20ohm) also. U7100 got warm so I replaced Inrush Limiter mosfets from a donor board (in this model there are 2 mosfets but in schematics it shows only one - Q7180). U7100 still gets warm. Measured...
Minor water damage. Replaced U5440. Otherwise everything seems ok.
The problem is that it never loads osx, neither from internal ssd or external and the fans starts to speed up after 1 minute or so.
Apples diagnostics comes with SMC error - PFM006. If it is sensor error how to find out which...
Okay. Do you have some other suggestion what it could be?
It confuses me that connecting external display the graphical error is away. I had a thought that liquid came under CPU causing this but it doesn't make sense.
VCCGT does't increase on internal LCD.
Could it be U7100? PPVCC_S0_CPU is only 0,6V when only internal LCD connected. It increases to 0,7V when also external display is connected. I read in a few other threads it measures 1,2V.
Area around U7100 was also touched by fluid. I had to connect...