12V electrical supply fault

[Lipek]

Hey everyone,


Wondering if anyone else has run into something similar. My Cupra Tavascan V2 (2 months old) broke down on 24 September 2025 with a “12 V electrical supply fault” warning. The car just refused to start and had to be recovered to my local Cupra dealer.

Photo: Error 12 V battery

Photo: Electric drive not working correctly

It’s now been over two weeks, and the car is still at the dealership. I was told they’re doing diagnostics and various tests that may take another week or so, and then the data will go to the manufacturer’s technical team for analysis before they even decide on a repair approach.


Has anyone here had the same 12 V supply or electrical system failure on their Tavascan?

• What was the actual cause in your case?
• How long did the repair take before you got your car back?
• Did the fix involve replacing the 12 V battery, a DC-DC converter, or something else entirely?

Any insight or experience would be greatly appreciated — it’d be good to know what to expect.


Thanks,
Greg (Lipek)

 

[Tell]

Fairly unique cars you might want to check for similar issues on the sister Vag platform cars just in case it's common or it could be a one off / low occuring issue:

Cupra Tavascan - Wikipedia

en.wikipedia.org

Might be some Ozzie sites as well. I recall Australia got it before it came to the UK.

Mind you, you might have checked that and drawn a blank.

Power of Google as a starting point:

Google Search

I see the AI engine picks up links plus the normals ones, then do it with ID5 instead of ID4. Staring point.