Seat Leon start stop error what could be the cause?

Hey, I had a similar problem with my Seat Ibiza (2015), and I also have a bit of experience with cars. My control unit was defective and I had to take it to the workshop. It cost me 1000.0 euros, but afterwards everything ran like clockwork again. The symptoms were the same - poor starting, high fuel consumption, warning light and flickering lights. The best thing to do is to visit the garage and have the fault memory read out. What exact model number and engine variant do you have? Best regards!

(Translated from German)

Hey, my Leon now has 187654 km on the clock and I just had it serviced last week. I could have the control unit checked. Do you still remember the error code? I hope it doesn't cost me 1000 euros too... Greetings!

(Translated from German)

Hey, unfortunately I can't remember the exact error code, but I think it was something with P06xx. Maybe that will help you a bit. In any case, it makes sense to have the fault memory read out before you start worrying about the costs. Sometimes it's a little less expensive or there's a simpler solution. Your mileage is already relatively high, so of course such things can happen. As far as the engine start-stop system is concerned, it could well be that the system has a fault and the battery is no longer charging properly. A low battery can also lead to the symptoms you describe. I'll keep my fingers crossed that it won't be too expensive! Best regards!

(Translated from German)

Thank you for the information! I'll probably have the fault memory read out as a first step and see what the mechanic says. Hopefully it's nothing serious and stays under 1000 euros. Your tip about the battery is also helpful, I'll definitely address that. Best regards and thanks again!

(Translated from German)