HIKVision DS-7216HGHI-SH bricked or dead?

domu

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Bought a second hand DS-7216HGHI-SH. Was told that just power adapter is missing.
I have added regular 12V DC socket in parallel, so I can use standard 12V connector.
In process I have noticed that all four 470u/10V caps were swollen, so replaced all
caps just in case. On board battery CR-1220 was flat so got replaced too.

Unit powers up, green power LED is on, can see ethernet activity on RX/TX LED,
red LED on board on but that's about it. Screen (both HDMI and VGA) blank.
Tried TFTP over LAN - no go. So, after reading some helpful threads on this forum
decided to try UART connection.

Now the interesting part. There are three 4-pin micro mini JST connectors on board.
Two of them follow a standard layout GND on pin 1 and 3.3V on pin 4. However
the connector J17 which is most likely an UART - parallel in row to the battery -
is pretty much dead - no Vcc, no any activity after power up.

Just to be certain, I have tested all three connectors with the scope. Other two are
changing state to high when power is supplied, but nothing happen on J17.

Is there anything more I could try ? Any helpful answers would be much appreciated.
 

alastairstevenson

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Just to be certain, I have tested all three connectors with the scope. Other two are
changing state to high when power is supplied, but nothing happen on J17.
Tx and Rx will be the middle 2 pins.
An oscilloscope is a good tool to determine which might be the serial console.
Normally, on power-on, both Tz and Rx will go to 3.3v, with Tx showing bursts to GND in multiples of around 8us as the firmware runs.

I have noticed that all four 470u/10V caps were swollen
That's not a good sign.
Was told that just power adapter is missing.
And neither is that.
I'd wonder if it's had the wrong power supply connected, maybe for a PoE model, 48v.
 

domu

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First of all, thank you for your prompt answer.

domu said:
I have noticed that all four 470u/10V caps were swollen
That's not a good sign.
would guess that it is a gentle attempt of "planned aging of the product",
as all other components on board are rather good quality, so is the design
and the board itself.

domu said:
Was told that just power adapter is missing.
And neither is that.
I'd wonder if it's had the wrong power supply connected, maybe for a PoE model, 48v.
good point, not sure though if 3.3V VRs would survive it, as LV seems
to be OK. Probably need to do some more testing.

domu said:
Just to be certain, I have tested all three connectors with the scope. Other two are
changing state to high when power is supplied, but nothing happen on J17.
Tx and Rx will be the middle 2 pins.
An oscilloscope is a good tool to determine which might be the serial console.
Normally, on power-on, both Tz and Rx will go to 3.3v, with Tx showing bursts to GND in multiples of around 8us as the firmware runs.
That's exactly what makes me concerned. There is no any activity on
on J17 on any pair combination, after power is applied.
 
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