Left headlights on (for a week) battery completely dead , charging now but headlights are flickering and clicking as I do it ,is this normal to. Yikes!

 

The behaviour of the lights is indeed perfectly normal IF you accept a nearly dead battery as normal. The death-throes symptoms of a battery in these cars are precisely the flashing and flickering of the lights...this symptoms come after all the others: random warning lights, seats, windows and locks malfunctioning, the touchscreen freezing or not coming into operation...the list is long. But the last cries for help are made visually by the exterior lights.

save yourself some grief. Your battery is probably ruined. Buy a new battery but *charge it fully* BEFORE installing it. New batteries are virtually never fully charged at purchase regardless of the salesclerk does or what he shows you (this is from personal experience with my 07 XK.
finallym get a CTEK battery maintainer (or simiar, but tgese are the best) and use it when the car is not in daily use. That eliminates any issues caused by low battery voltage.

 

Thx disconnected cable from battery and recharging it while it's disconnected hopefully battery ok just a year old

 

yeah it may survive. 12.6 volts minimum. If you don't need the car, fully charge it and leave the cable off for a day. If you still have 12.6 volts you're prolly ok. I presume you have a battery tender also?

If you have to buy a battery, buy it a day in advance and have the auto parts store fully charge it for you. They will at no cost. Then have them show you the resting voltage and let them install it if you trust them not to scuff your bumper. (heck they weigh 50 lbs.! They will also put the battery in for no cost and keep the old one.

Edit: I'm going to add that I'm in agreement with Gregory's recommendation above. Save yourself the grief and get another battery, but if money's a factor....

 

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