DVR no video

[digitalpc]

Hello everyone,

I have 20dvrs with no video no sound, they turn on power light on and cooler working.
Im searching for problem about 3months and i thing is bios/firmware problem, but they have different chip bios with to much legs.
can i programm firmware/bios with usb or any programmer via usb, vga, hdmi or any method
i need your help

thanks anyway

[diif]

Re: DVR no video

Some details like make/model and photos might help.
The DVRs I had to repair when I worked at a CCTV place were mainly dead due to poor quality power supplies that had burnt up components on the board.

[digitalpc]

Re: DVR no video

all are dahua cctv 2011 2012 2013 model

[petehall347]

Re: DVR no video

have you tried removing the battery for a while and testing it whilst out ?
maybe try a different power supply

[digitalpc]

Re: DVR no video

have you tried removing the battery for a while and testing it whilst out ?
maybe try a different power supply

i try but no working

[diif]

Re: DVR no video

I can't read any of the markings on the ICs, what's on the BIOS chip ?

[digitalpc]

Re: DVR no video

I can't read any of the markings on the ICs, what's on the BIOS chip ?

mx25l12845emi

[repelecras]

Re: DVR no video

i have the same issues with my CCTVs. All of them have power but no video. what diff said might be right, poor quality power supplies. I am in the process of troubleshooting the boards inside the cameras. Hopefully the electronics can be fixed.

[diif]

Re: DVR no video

mx25l12845emi

Have you tried pulling off the BIOS chip and using a reader ?
A CH341A will read those chips.