Few days ago a new alternator was installed at the local Toyota dealer. Car was driven for couple of short trips afterwards and performed perfectly. Now after being parked for 3 days it is completely dead. No remote, no dash light, no signal of anything. I used mechanical key to open the door and than tried starting up with the key fob. Nothing. Key batter is only few months old. Car battery was in excellent shape just a few days ago. Where do I start...? New battery..? Could it be related to the new alternator install, wires, fuses...? Or maybe engine immobilizer system...? Unlikely though since there are zero dashboard indicators on. Car is completely dead.
Any advice most appreciated