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EEVblog 1520 - Troubleshooting a Faulty BM786 Multimeter

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Looking at a faulty returned BM786 multimeter.
Warning: Some components were harmed in the making of this video.

That might be a possible short from manufacturing. Seems to be under the pins. 

edit: nah, looked again at other frames and seems like it is gunk that you scraped earlier.
also can the micro pull it's own rails high? shouldn't the on signal come from some other chip/circuit?
there was also another rail that was coming through an inductor, can't remember if you measured that. if the enable for the rail doesn't happen there might be other stuff that's not enabled.

Best two shots I saw of it.  Maybe damaged during the testing or maybe fine and just looks like the back was blown off. 

Offer stands.  If you would like the Keysight for parts to repair yours I'll swap you.   

Someone had posted a link to a better view of U2.   Looks fine. 

Had another look at the video and I don't see you measuring the other rail (photo 1).
Also the line (photo 2) that should latch those +/-1.65V rails might very well be RESET which is low. Even if you manually enable those +/-1.65V rails all micros might be in reset. 
Those +/-1.65V rails seem like VACC for an ADC. So the other line might be the 3.3V digital for the chip. If that's missing, or RESET line is low, it might explain why you're getting nothing from the micro. 
So RESET might be low because of a bad voltage supervisor chip / part of its circuit.

In the youtube comments, Dave verifies multiple hacked/missing/etc components on this meter.
Either production quality really slipped here, or someone did try to mess with it.

This would be one benefit of having a tamper sticker, not a "warranty void" one though.


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