Bad DVR, bad caps on a Swann-SWDVR-41300H-DVR symptom video and web working but no Hard Disk recording / playback even with a new hard disk the problem is the power supply for the HD inside the unit.

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Today someone asked about an old DVR for a security system it worked but the HDD recording did not work. Its and IP based unit with a small Linux based SOC made by SWANN.

First I thought bad external Power supply, I checked that and

1) the voltage on the output was fine both with and without the DVR connected
2) providing an external power supply to the Hard disk made no difference even though it was a known good HD

So I knew the problem was INSIDE the unit. Opening the unit up I was clear the electrolytic capacitors were bad due to the bulges (see photo) there were 3 bad caps they were the same rating: 16V 1000uF 105 degrees C. They were a cheap no name brand with the heat from the HDD / Controller and 24x7x365 running it was no surprise they failed.

They were large through hole caps. I desoldered and replaced them. HDD sprung back to life. It would not record still but the system reported the size of the HD (500G) and on power up it made the sound of an HD spinning up. In the menu system I selected the option for device management, then HDD and it was reporting unformatted. So I selected format. A few minutes later the format was done and recording was restored.

The vendor SWANN has a guide that suggest the HD might be the problem, I'm sure their design, thermals and cheap capacitors have ended the life of a number of these units.

A few people asked and the electrolytic cap is the component between the cross head screw and the back of the ethernet port. The shiny metal top of the capacitor has a cross cut in the top to allow venting without an explosion if the cap goes bad as this one has. Note not all caps bulge like this when the go bad, you need to test the ESR of the cap.