SkipperEye

I tested with a voltmeter on my Octavia iV - the HV battery will trickle charge the 12V battery, but only if the ignition is on or the HV battery is charging. The problem that I had, was that the radiator fan was coming on full when the HV battery was charging. This fan runs from the 12v battery, and was taking power faster than the trickle charge was replacing it, so once it goes below a certain level you can’t turn on the ignition to balance between the two batteries. The recall fixed it.

Re: the 12v battery going flat, I’ve just had this through today from my local dealer: “We have just been notified that Skoda have today released a new recall in regards to the Battery monitoring system, the recall is for the exact same issues you have been experiencing lately. We have been asked to replace the battery monitoring control unit as part of the recall & I have ordered the part ready for your visit to us on Wednesday.”

I have the exact same problem with the fan running when the HV battery is charging, which runs down the 12v battery. My local Skoda garage have reported this to Skoda Technical who have replied saying they are not aware of any such issue. Is there any more information that you could give me so they can tie my case to yours?

I had the exact same problem - my alarm was going off during the night and my neighbour told me that the fan was running when the car was charging from the wall point. The next morning the car was completely dead. Roadside came out and diagnosed flat 12v battery, and found three pages of error messages in the fault memory. They arranged with the local dealer for the vehicle to go in for the big software update. Since it’s been back I’ve had two “front assist unavailable” errors, and today the infotainment system turned off on the motorway without warning.