Synology DS1817+ power supply death...happily now back!!

Looks like my trusty Synology DS1817+ which has been going strong for many years, has suffered a severe power supply fault and died. There was a mains fault (trip and reset a minute later) that probably was the straw that broke its back - and it was running OFF the UPS at the time, as that needs new batteries...

I'll do some surgery later and see if there isn't an obvious fuse inside anywhere which has blown, but looks like I'm power supply shopping.

Just hope the rest of it is OK 😭

Edited by Pheasant (Wed 13-Nov-24 21:19:30)

Well there's not a trace of black soot in there at least, but not much else obvious either (to the untrained eye). I'm not messing about with a mains powers supply.

Have ordered a new PS and hopefully it will restore it to life,

Did you test the power supply with a multimeter?

There’s a thread here (slightly different model) that might be relevant: https://community.synology.com/enu/forum/1/post/1318...

Thanksfor the link. As far as I can see they're referring to a DS1815+ there, which is a generation older than mine, hence the chat about the Atom bug and soldering in resistors etc.

Here's a video of one getting pulled apart. Unfortunately the Mobo position on the later DS1817+ is right at the bottom of the unit, underneath all the drive bays. A real pita (not bread) to get into.

I can just sneak a peak at the CMOS battery here, but its too tight too get both probes from a DMM on there from outside. So it will need to be further surgery...

Surgery (and googling) continues...🤣

Mobo is out. Wasn't actually all that bad after all. Simply required the bottom cover fully removing (6 screws) and then take out 7 securing screws. After that disconnect carefully release one micro ribbon cable connector and gently lever off the Mobo from 2 remaining IDC connectors from the drive backplane. Or something like that!!

Checked the existing 2032 CMOS battery. Reading was 3.2032 V. I think it's OK but while I was in there have replaced it with a 'fresh' (well it was in a packet in my battery box!) Energizer 2032 button cell which is reading 3.314 V according to Messrs Fluke.

Now I'm in actually some doubt as to whether this board may be suffering from the dreaded C2000 Atom series bug.....more googling before putting it all back together! 🤣

Power supply check now. Out of the chassis test: it's powering up / fan is running when green + black are jumpered. All the +12V and +5V outputs I've checked look OK too...

Leads me to suspect it's the power switch sub-board or Mobo. I've read some stuff about a faulty transistor on the DS1815+ units....

Apparently you need to test 2032 cells with a small load (say 100 ohm) to get the true (actual depleted) voltage. Testing with them just open circuit apparently doesn't tell you much, as a fully depleted cell can still measure 3V (unloaded with just a DMM) but when a small load is applied the voltage drops like a stone.

That's something I've learnt today. Also how to switch on an ATX-type power supply through the header pins!

Edited by Pheasant (Wed 13-Nov-24 20:14:58)

you can get a little plug thing or you can make your own. some high end psus have a connector to power up two psus simultaneously

I made a DIY jumper with a bit of wire I had lying around. That was good enough for this evening's little job.

Anyway am pleased to say the new CMOS battery did the trick. We're back in action and fully operational - on the kitchen floor and topless 😂. But fully running nonetheless!!

Wooohooo.

Edited by Pheasant (Wed 13-Nov-24 20:57:47)

Good news.

Somewhere in the back of my mind I seem to remember a similar problem caused by the CMOS battery - but I can’t recall whether it was one of my Synology NASs or something else.