Hello, I have a 2019 macbook a2141 with no backlight. video image is visible with flashlight but no backlight. All the associated circuitry is located on the back side of the logic board. I've removed the logic board and display and have them connected together on the bench so I can probe the back side of the board. I'm applying power through a usb-c port attached to the logic board but I'm not sure how to actually boot the logic board. I tried attaching the power button and that didn't work. I also have the fans attached and they are not spinning. If anyone can help me with this setup I would certainly appreciate it. Thank you.
2019 macbook a2141 backlight troubleshooting
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Re: 2019 macbook a2141 backlight troubleshooting
See attached -> locate one of the 2 power buttons that should be a low profile surface mounted pushbutton.
Press it and confirm that you can see the display graphics without the backlight.
Then carefully confirm the voltage to ground of:
ISNS_LCDBKLT_P
ISNS_LCDBKLT_N
BKLT_EN_R
PPVOUT_S0_LCDBKLT
Is your keyboard backlight working? The same backlight controller on this model appears to drive the LCD and the keyboard backlights. -
Re: 2019 macbook a2141 backlight troubleshooting
Hi mon2, I didn't see an attachment. I did not realize there were surface-mounted pushbuttons on the logic board. I will look for them. This could help me greatly. I don't know if the keyboard backlight is working because it may have been disabled. I received this macbook not working. Thank you!Comment
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Re: 2019 macbook a2141 backlight troubleshooting
Further information - I do not have PPVOUT_S0_LCDBKLT voltage - should read 59V, I read 0V. Also do not have EDP_BKLT_EN. And furthermore, BKLT_SD reads 12.5V (should read 0V to turn on Q8400 to pass 12.6V to backlight boost).Comment
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Re: 2019 macbook a2141 backlight troubleshooting
Tried the onboard pwr button (actually these was no switch, just two pads) to no avail. I cannot seem to get the logic board to boot on the bench. If anyone has successfully booted an a2141 logic board out of the case please let me know the setup. Maybe I should have done an NVRAM reset and/or SMC reset before disconnecting the board (?). Although without a battery connection it seems the NVRAM would reset on pwr up.Comment
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by cheebsterMacBook Pro 2019 A2141 820-01700 NAND Issue Stuck in DFU
Ok, here's an issue ive got on a A2141 820-01700 MBP 16' 2019. No signs of life, 5.06v 0.0a on usb-c meter, on each 4 usb-c ports.
Nand voltages are missing.
I've found no shorts at all so far, no signs of heat via thermal camera either.
PPBUS_G3H 12.31
PP3V3_G3H_RTC 3.387v
PP3V3_G3H 12.31v
PP2v5_NAND_SSD0 0v 58 ohms
PP2v5_NAND_SSD1 0v 57.8 ohms
PP1v8_SLPS2R 1.8v
PP1v1_SLPS2R 1.1v
P3V3_G3H_SOCPMU 3.37v
PP0V9_SLPDDR 0.9v... -
by tomtom67A friend brought his fresh-from-ebay macbook pro A2141 after he failed replacement keyboard plugging.
I fixed all the little problems he introduced.
I am unable to install macOS to this device. Both Sequoia and Catalina (from Internet Recovery) start to install, but after ~2-5 minutes into the installation the macbook does a hard restart (max fan spin for a split second, then reboot without chime).
I noticed what I think is a very high power consumption, like 20V/1.7A when activating WiFi for internet recovery, and more like 20V/3.7-4.1A while downloading the recovery... -
by martyjelenHello, I have this Macbook A2141. It stuck at 5V / 0,075A. I measured all 4 ports, all the same. PPBUS_G3H is present but only 12,3V. Should be 12,6V ? according to this article : https://repair.wiki/w/MacBook_Pro_A2...w_at_5V_repair
PP3v3_G3H_RTC_X is present - 3,3V
PP3v3_G3H_SOCPMU is present - 3,3V
​What else should I check?
Thank you for your help. -
by rathore4uHi all,
I am trying to fix a T2 Macbook A2141 820-01700 board that's stuck in DFU mode.
The SSDs have correct voltages
PP2V5_NAND_SSD0 = 2.5V
PP2V5_NAND_SSD1 = 2.5V
PP0V9_SSD0 and PP0V9_SSD 1 = 0.9V
PP1V8_SSD0 and PP1V8_SSD1 = 1.8V
I can force the laptop to DFU mode using the SOC_FORCE_DFU using SWK003. Apple Configurator 2 tries to restore the Mac but it fails back to RECOVERY.
Looking at the diagram here - https://repair.wiki/w/Apple_T2_platform Step 6, it says the problem could be loading from SSD,... - Loading...
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