Good evening…. I drive a Citroën c4 Coupe bj 2005. For a short time I have had problems with the electronick. It started so that the tailgate could not be opened any more. I did all the cables and measured through. Everything was OK. Then I blew the lock and was the same. Then I blew the button and still nothing. Shortly afterwards I noticed that the car started hard. All the settings were at zero. Clock… Date…. After leuc hten of headlights does not work….. Interior lighting does not work when the door is opened (except when the car air)…. Central locking with remote control does not work…. Nothing works anymore…. Every time the car is switched off the clock goes on at the new turn on…. Date ….. To zero…. Starterbatteri new in…. Please for help….