Having replaced the main battery on the Dacia a little while back, frustratingly the 'Warning, check SOS' error keeps coming back. 

I had hoped this would go away, but clearly not. Some more investigation was required, though being relatively new there wasn't a load of info out there about the specific problem. What I was able to dig up was that this was a fairly common issue on similar-age Renault Clios, which share a lot of their parts with Dacias like mine.

Apparently the SOS button - which is intended for if an occupant has a medical emergency and the driver is not sure of their location - has its own sim and battery pack which lives behind the instrument cluster in the dashboard. Removal (on a Clio) looks fairly straightforward

- Lower the steering wheel to its lowest angle

- Remove the instrument cluster surround by pulling it sharply towards you

- Undo 4x torx head bolts to release the cluster from the dashboard

- Pull the cluster towards you carefully until you can access the wiring harness & unclip it. Then pull the instrument cluster out

- Reach into the deep dark depths of the dashboard and there is a black box. Unclip various wiring harnesses then pull it out to instrument cluster hole

- Open it up and it has an 18650 battery and short wiring harness, unclip it, pull the battery out, replace it and then reverse the above steps.

Finding the part number of the battery, and if there are different variations, is proving difficult right now! I'm not sure if this is covered under the warranty or not, so I need to call Dacia and see what they say. If its a warranty job then happy days (other than the minor inconvenience of being without the car for a day while they replace the battery) - if not then I'll give it a go myself and see how I get on. I suspect it will be a case of take it all to bits to get the part number off the existing battery, reassemble it again, order the new battery, then do it all again but I can't see any other way unless I can tease a part number out of the parts dept of my local dealer.

Its really almost a cosmetic issue - other than the error it flashes up on the dashboard it doesn't affect the car at all; but the fact it puts the spanner warning light on gives me a twitch so I'd like to get it sorted out. If it just needs a new battery then it shouldn't cost much more than £20 and an hour of my life. If. IF...