Hardware Dead board no short found

Daroxx

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Hey folks,

I have a HAC-CPU-10 board here which does absolutely nothing. I couldn't find any short and I already changed M92T36 and BQ24193 with known good ones (they both work on another board). No fluid or prior repair could be detected.

The main problem is I don't have the main power rail futher than the measure point directly over the usb port. That's it. There are 5V and nothing else. No voltage on the battery connector, the BQ24193 or the M92T36.

I think I checked every capacitator and did diode measurement on the pins from the 2 ICs but I couldn't find any suspicious value (compared to the known good board).

The only difference I could find on this board is the following part, which isn't present on my HAC-CPU-20. I attached 3 pictures and I hope someone could give me a hint, since I have no clue from here.

Is there any schematic on where the power rail goes from the meassure point directly above the USB charger.
It seems that there needs to be some power on signal which seems to be missing, but I have too few experience with those boards, so maybe can help me out.
 

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Daroxx

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Actually the main default was the fuse directly above the usb charger. Changed it and now it charges again. I checked the status with TegraRCM and it says ok. So Now I only need to fix the display connector and I'm good to go.
 
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peepy

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Actually the main default was the fuse directly above the usb charger. Changed it and now it charges again. I checked the status with TegraRCM and it says ok. So Now I only need to fix the display connector and I'm good to go.
Which thing is the fuse people. Always talk about it but I never know where itinerary also how do you test
 

Daroxx

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This is the fuse or filter. I checked it for voltage. Had Voltage on 1 side but not on the other side. And since it is basically the only connection between the charging port and M92T36.
 

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