[Meg]

My C-HR is 9 months old with 2000 miles on clock. After one week in garage would not start.
AA called and got it going. Service engineer says I must purchase a battery charger/ maintainer and to leave car unlocked as alarm drains battery. This, to me is ludicrous advice! What's the answer?

 

[zx10guy]

There was another member that seems to be reporting similar battery related issues. It appears when the car is "off", that there is still some power draw by some of the electronics in the car.

Later model BMWs are well known to keep pulling significant power from the battery with the car shut off. The fix is if the car is going to sit for a while to put it on a trickle charger/battery tender or to remove the negative battery cable.

I know it seems ludicrous to you but it looks to me that you'll have to either get a battery tender or remove the negative battery cable.

 

[DrZeus]

I was surprised when my 2018 sat for 4 maybe 5 days and killed the battery. 37,000 miles. Mind you, it will be 3 years old in July so it's not too much of a stretch for battery life as far as averages go but, my previous vehicles lasted longer.

 

[Peter Brennan]

My C-HR is 9 months old with 2000 miles on clock. After one week in garage would not start.
AA called and got it going. Service engineer says I must purchase a battery charger/ maintainer and to leave car unlocked as alarm drains battery. This, to me is ludicrous advice! What's the answer?

We had the same issue with my wife's CHR hybrid last year, 1 dealership wanted to change the battery without testing it another tested it and reported that it was fine. The problem occurred three times and it was recommended that we should sit on the drive with the car in ready mode for a hour every few days (Toyota) (in sub-zero temperature I think not) another suggestion was to use a battery charger (difficult with the car on the drive!) another suggestion was a solar charger which we bought, paid a Toyota dealership to install a wire into the cab so we did not have to attach to the battery. Everything was OK then after a period of dull weather the battery was unable to start the car AGAIN. When we got it going I noticed that when the charger was fitted and the sun was shining the interior light came on even with the doors closed! The only way was to switch the curtesy light off so it does not come on when the doors are open!

I am not clever enough to check but wouldn't the fact that the light was going on even when the door was closed suggest an open circuit past the door switch, perhaps not big enough to bring the light on but enough to drain the battery over a period of time. Someone with the correct knowhow could problem check!