How might I test the high side mosfet to confirm that it has indeed failed and destroyed the board?
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mon2 Do you have any final suggestions for this bad boy or should I call it quits? I truly appreciate all your help. It's been a great learning experience.Comment
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I think it is a 'dead horse' but you can confirm the same by applying a voltage onto the removed downstream fuse pad @ 0v8 or even 1v0. Then check who is heating up. It should be anyone with the 0hm or similar low resistance to ground. Respectively, that same leg was most likely hit by the original highvoltage feeding the high side mosfets that are often present on the buck converters,
Some buck converters have internal high side and low side mosfets; while others have these parts external. The devices with the external mosfets do so to support higher peak currents - like the CPU / GPU power rails.Comment
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please check the ssd power section this board has only the ssd getting short check the impedance of the inductors of the ssd supply.Comment
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The only time this ends well with SSD power rails is if you have a shorted cap on the 2.5V rails (which is very common due to the fans sucking in dust etc over the both sides of the board). If however that short is also transposed to PPBUS_G3H, then it's usually game over. A shorted 2.5V SSD regulator will fry the NAND's.
Additionally, these machines have the CPU/GPU MOSFETS at the upper side of the board, and boost components for each DRMOS correspondingly close as well. You only need a very small amount of corrosion here from liquid etc to have catastrophic failure due to changes in the boost circuits. Last week I had a very small amount of liquid damage to U7230/R7239/C7239 on a 820-1700 board with U7230 shorted (and dead CPU as a result). The rest of the board was clean but that's all it took.
Apple used to some protection in these areas on the older models but there is nothing there now. For such an expensive machine there are lots of booby traps.Comment
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You right. This is the worst machine they have built as there is always corrosion on the ssd side so the dust accumulates that area and 90% of the time takes away the ssd and what makes it worse is they have glued the ssd with epoxy.Comment
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Hi everyone,
I have replaced a broken display on A2141 with a good one, taken from similar model, now the image and backlight works fine. But the camera, the true tone and keyboard backlight is not working. I made some research on internet but I am still not sure how to fix it, according to logiwiki the A2141 display is compatible with all similar model but we need to use a1707 flex cable, so my questions are:
1-does the cable will make every thing work fine ?
2-Do we need to swap display IC chips from the old display to make everything work correctly,( I saw it on multiple video... -
I HAVE A MACBOOK PRO A2141 820-01700 THIS BOARD IS PP2V5_NAND_SSD1 SHORT TO GROUND THEN I CHECK ONE SIDE U8600 IS SHORT THIS SIDE IS ONLY ONE CHIP U8600 OTHER SIDE
PP2V5_NAND_SSD1 IS OK AND U9100 U9200 U9300 U9400 IS ALSO OK Will removing the U8600 fix the board or will I have to install a new one
Link to boardview --> https://www.badcaps.net/forum/troubl...91#post1449091 -
Hello friends, it's been a while.
Model A2141 came to me for repair.
I confirmed that there was a short in the ppdcin line and that the capacitor was blown.
All the short line capacitors seemed to be in bad condition, so I replaced all c7043, c7024, c7026, c7027, c7029, and c7042.
The short is caught and the power is turned on.
However, when the power is turned on with the battery installed, only one charging port works and the other three display 20V but 0 amps.
If you plug in the charger when the battery is not installed... -
MacBook 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... -
Got an A2141 MacBook Pro 16" computer turns on however the track pad clicks but the keyboard has no life, NO LIQUID DAMGE whatsoever. Trackpad does click but the OS loads but the trackpad won't move the cursor, the keyboard is unresponsive. I replaced the cable and the trackpad to see if that was the issue but it was not, I went to see if the CAPS LOCK would turn on but it does not. Any indication what this is? I went and tested the lid sensor but nothing else. Battery holds a charge, fans spin normally, and lcd is good. I can use external mouse and keyboard without issue....
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