This follows on from my thread , "no electric drive". It applies to the MY25 PHEVs

My 2025 Superb PHEV lost electric and engine drive after 2 weeks of ownership. Fortunately I was parked at home.  It was recovered to the dealership by low loader the following day. (Skoda assist and Enterprise car hire another story!) I will mention the AA diagnostic system would not connect to the car so no diagnosis possible. I managed to get the car working for it to go on the low loader the next day by fully charging the 12v battery. 

It transpires there is a Skoda technical bulletin warning this problem may occur if a particular EV charging scenario is followed. Skoda are keeping this very quiet and as yet have no fix.

Over the following week the dealership ( who were very helpful and communicated what they were doing)  proved this scenario caused the electric and drive systems to fail. 

So what is this scenario:

The 12v battery should charge when the engine is running or the EV battery is on charge. Having parked up the car if it is then left standing for more than 6 hours and then put on charge the 12v battery is NOT charged but DEPLETED. When the car is then started the 12v battery holds insufficient charge for the "systems" to work and all drive is lost. 

I am collecting my car this morning and will "work around" the problem. I have registered that should I breakdown away from home or Skoda do not fix this problem urgently then I will be forced to reject the car.

Skoda customer services are supposed to contact me today with an update on timescales to fix the problem - I am not hopeful...

 

Additional info:

I do not know if this applies to other Skoda models with the same PHEV system or ALL Superb PHEVs. Bad batch? Also if it applies to VW models with the same PHEV set up.

I do not know if it applies to DC charging. 

12v battery drain in PHEVs is a common problem to many brands when the car is used a lot in EV mode. - I experienced this on my previous car, not Skoda. The difference is that most PHEVs allow selection of EV or engine drive or both (hybrid). The Superb does not allow engine only drive - something I wish had known. it means you cannot reserve EV power for city use after driving to the city for ex. 

 

I will see how things go and update accordingly.

 

 

 

 

Update:

Collected my car this morning all working, but no update when fix may be available.

Supposed to get an update from Skoda CS but not heard from them this morning.

 

Did learn:

Problem does not apply to DC charging.

It is possible to set a reserve EV charge level for later use. If set to max charge the engine operates the majority of the time - tried this on my way back from the dealer and it works. 

 

Planning to measure/monitor the 12v battery level to see if discharging when parked up and when charging the EV battery.

 

After several calls to Skoda CS regarding this problem they could offer no date for when a fix would be issued. In the meantime more warning messages appeared if the car was not used for two days - I think due to the 12v battery becoming v low. After 4 days unused I had two more problems - the drivers window would not shut when opened briefly, it would bounce back to half open and required a shutdown/restart. The second problem was the car refusing to power up - after 3 attempts it said move the steering wheel ! It then started?

I decided a week ago to reject the car and learnt later in the week this had been accepted. (I had reserved the right to reject the car when it broke down after just 13 days of ownership). For the 2 months I had the car the Skoda dealership were very helpful and supportive - something I was very grateful for.

A great pity as I liked the car very much but had no confidence in Skoda issuing a fix(es) in any reasonable timeframe.