[anhizer]

I have been noticing a few issues with comfort access and starting the car over the last few days (sometimes needed to unlock the car by pushing the unlock button on the remote, sometimes needed to present the key to the steering column to start). I figured the battery in the key was low so I went ahead and replaced they battery with a fresh one. Now that i have replaced the battery the comfort access and starting does not work at all; I haven't had a chance to see if my other key still works (ill check that tonight). I can still remote unlock and lock the car using the key buttons so the key battery seems to be OK. I can also still start the car by presenting the key to the steering wheel.

If my alternate key is working ill try another new battery and see if that fixes it but if not i assume its something with my key. If neither key works perhaps its something with my car? Anyone have any experience with this failure?

Worst case ill take it to the dealer but im out of warranty and would rater not pay their shop fee to evaluate it.

TIA.

[Billfitz]

Those are symptoms of a low battery charge. If you were in a cold climate that could explain it, but as you're not it's something else, and probably not the battery since a new one gives the same result.

[anhizer]

Originally Posted by Billfitz

Those are symptoms of a low battery charge. If you were in a cold climate that could explain it, but as you're not it's something else, and probably not the battery since a new one gives the same result.

Low car battery charge or low keyfob battery charge? I assume you refer to the keybattery- I know I have had similar issues in the past (unresponsive comfort access) and they were remedied by replacing the key battery. It's possible the new battery is bad (or maybe i have a dirty contact in my key?)

There isn't any sort of pairing procedure i need to complete after replacing the battery is there? i looked in the manual and it only references the battery replacement procedure and nothing else.

[Billfitz]

When the car battery is low it disables some of the car features so that it will still start the car. That could be what's happening. A new car battery must be registered. Failure to register it won't cause the problems you're having, but you still need to get it done. The problem could be your fob battery, what happens with the other fob?

[anhizer]

So I went home and tried the second key and it worked fine. I checked the new cell with a battery tester and it tested fine as well. I took a close look at the key and the battery contacts were dirty so I used some contact cleaner on a bit of paper towel and cleaned the contacts. Reinstalled the battery and now the key is working properly. I’ll keep an eye on it but my guess Is the dirty contacts were causing a poor connection. I went and checked the old cell and it was still in the “good” range but also in the “bad” range. It’s possible that the old cell is still good but for a few bucks on the battery it’s nbd.

[1QuikWS6]

Don't know if this a year specific thing - but you shouldn't have to guess when your key fob needs a new battery - the car can tell when fob battery is getting weak & it pops up a warning when you 1st start the car - gong with text on dash 'remote battery low-replace' & pict of low battery

Warning triangle will stay up on dash until you replace battery.

The warning will be located also in iDrive under Vehicle Info/Check Control

At least that's how it works in my 2015...

[anhizer]

I didn’t see any notification; my car is a early model (late 2013) so it’s possible it doesn’t have this ability. I did check for notices; the only one I saw was the key wasn’t found (have to present it to the column). After cleaning the contacts the key seems to be working properly for the most part. This morning it did take a couple of presses to start up but no other issues since.

[jkwhar]

I have a MY 4/13 and get the "low battery" notification on my cluster and idrive.

[coupedream]

I got the battery low indicator on my 2015 435 gran coupe. I replaced the battery with one from Walmart; same type. since then comfort access was some timey for about a week now it doesn't work at all. not even the tailgate. does anybody know where the comfort access fuses are?

[batterykid]

I had this same issue after a major cold spell in Seattle. Comfort access wasn't working anymore, but I could start the car by holding the fob near the steering wheel.

I ended up getting a trickle charger, and replacing the battery in the fob, that combination seemed to do the trick. Not sure which was the fix, but the fob battery was low in voltage, and so a fresh, greater than 3volt, new fob battery did the trick for me.

[parusa]

Originally Posted by batterykid

I had this same issue after a major cold spell in Seattle. Comfort access wasn't working anymore, but I could start the car by holding the fob near the steering wheel.

I ended up getting a trickle charger, and replacing the battery in the fob, that combination seemed to do the trick. Not sure which was the fix, but the fob battery was low in voltage, and so a fresh, greater than 3volt, new fob battery did the trick for me.

I'll have to try this. i'm in the seattle area also and i've had issues with my comfort access since early march.

[Migelito]

Fellas, I have to confirm the dirty contact extreme sensitivity.
Here is the story: my 535xi 2015 F10 car was showing low battery on the key. I replaced the one with a new CR2450. Tried to access the car and no luck, only through buttons. To start the car had to hold the key at the column, whose position was extremely sensitive to begin with. After reading what you all wrote, tried to give it a change: removed the new battery, wiped a few finger prints (!!!) with a cloth, wiped gently the "+" and "-" contacts inside the key, replaced the battery back and: the car now can sense the key, comfort entry works, car starts without the key at the column.

the lesson learned: be careful with the fingerprints, and just wipe gently the contacts inside, place the battery nice and firmly in against the contacts.