360 dash malfunction

Guy's,
Just wanted your experiences in relation to something I have experienced today and another long standing issue.

I am aware of how fragile the electrics are on the 360 and how important it is to have a fully charged battery. I know what damage can result from a weak or low battery as its been documented on here several times before. I drive my 360 approx once a fortnight and have it on a battery tender/conditioner via the cig lighter to help keep the battery in top condition and reduce load on the alternator. I have used this battery tender without issue for over 2 years. (It charges at 1A to 14v and then discharges to 13v before starting the charge cycle again etc, etc).
Anyway I took the car out for a drive today (1st time in almost 2 weeks). No issues and enjoyed the drive. When I returned home I got out of the car and left the drivers door open. I then opened the passenger door and plugged in my tender before closing the door. While walking back to close the drivers door I switched on the power to the tender. (Usually I have both doors closed before I switch on the power to the battery tender). When I did this I could hear a clicking noise coming from the dash. I sat in the car and noticed that the clicking noise was corrisponding to a flashing of the mileage display on the odo and certain lights on the dash! I then closed the door and the clicking stopped as did the flashing lights. When I then opened the door, the interior light came on and the clicking and flashing started again, so it was initiated by the door being opened (I am thinking current drain to interior light?). I then jumped out and disconnected the battery tender. I jumped back in and started the car, started up fine but nothing on the dash worked. No guages or lights what so ever!!! I stopped the car and opened the door again to be greeted with the clicking and flashing!
I decided not to panic and went in for a pot of tea. Once refreshed I checked all the fuses, all ok. So I powered down the electrics with the switch under the hood. I returned after approx 60mins after searching Fchat for any simular experiences (which I didn't find). I reconnected the power via the switch and went to start the car. Opened the door and no clicking or flashing lights. I then started the engine and (thank the lord) all was back to normal. Dash ok.
Have any of you guy's experinced something like this before??? Do you think that by leaving the door open when I switched on the battery tender I caused a current spike??? Possibly because the battery was being loaded by the interior light at the same time when I switched on power to the battery tender which would have given power to the battery. I am now quite paranoid.............I went back and disconnected the power switch under the hood and have not put my tender back on.

Another funny issue (non related) is that when I switch on the lights at night I get a clicking sound from the dash! I have always had this noise since I bought the car several years ago so I don't think its an issue. I am just interested to see if other people have experienced this! My car is a 2000 360 manual and it is fitted with the Xenon light upgrade from the factory.

Your thought to either issue are greatly appreciated.
D.

 

Cheers, it's good to know I'm not alone!