Post
by smickell » Sun Mar 06, 2016 11:31 pm
First post here, came across this thread after looking all evening for comfort access & battery drain problems.
My 2011 E70 (which I've had a year today )was in recently getting the comfort access security update. My driver's door comfort access wasn't working and I knew that at purchase, but the first time I went to use the passenger door after the update (about 3-4 days later) the passenger door had stopped working too, both for lock and unlock. Not only that but when locking by touching the grooves on either of the two rear doors, it takes about 2-3 seconds for the car to lock now whereas before it was instant, or near-instant anyway.
About 5 days after the update I started seeing the 'increased battery discharge' message and now most of the time the comfort access doesn't work at all; it does if locking and unlocking within maybe 30 minutes of a drive. Every journey I make in the car is at least 15-20 minutes so it should be getting plenty of charge. If switching off the ignition but keeping the radio/phone on, they shut off after about 2 minutes; never a problem in the past.
The dealer looked at this and it transpires that the passenger door handle is now faulty, simple as that. Also after leaving the battery on charge overnight and for over 20 hours of charging, it only reached 55% which indicates a faulty battery. I'm not sure if the battery was isolated from the car when doing this charge; I'm guessing it wasn't, and that something is continually draining the battery. That 'something' being the comfort access. Some sort of internal logic is then disabling the comfort access as it realises it's causing a battery drain. Does this not sound reasonable? I just ask because the dealer is going to replace the battery...