Keyless Entry & Lock Stopped Working - Why?

[amusante]

So this morning, my doors did not automatically unlock when I pulled on the handle and I had to use the key to unlock the car. This is the first time I have experienced this issue. It has continued to do this the 3-4 more times today that I went to open my locked door. As of now, keyless locking feature has also stopped working. I touch/push on the little square on the handle and nothing happens. I also have to use the key to lock the car now.

Does anyone know of any known issues that would cause this or is my key battery dying/too low?

Any help is much appreciated, thank you!

[Silverbullet S4]

Dead/dying fob battery.

[gtg196w]

This happens on both sides/all the doors? Did you ever get a warning when you started the car in the last week or so that the key had low battery? Have you tried opening with your other key?

[b6onboost]

I have a 2013 and have already replaced the key fob batteries twice. Both times received the low key battery warning though. (Dealer replaced them both for free, each time.)

[amusante]

This happens on both sides/all the doors? Did you ever get a warning when you started the car in the last week or so that the key had low battery? Have you tried opening with your other key?

I just tried the driver and passenger doors and it did not work. I did not have any warning about the key. I also haven't been home yet to give the other key a try.

[Silverbullet S4]

Mine didn't give me any warning either. I went to lock my car and couldn't lock/unlock it with the fob. I could start the car though luckily, which was a concern at first.

[will13k7]

car battery could be low too, when it goes into a low-power mode, the door sensors get shut off.

[TexasDfwS4]

Check the fuses and if VAG-COM check is a code is present.

[jl87]

car battery could be low too, when it goes into a low-power mode, the door sensors get shut off.

This. Or remote.

[amusante]

car battery could be low too, when it goes into a low-power mode, the door sensors get shut off.

Any way to check battery level? I miss my voltage meter in my B5 S4

[jl87]

Via MMI hidden menu or Vagcom.

[will13k7]

Any way to check battery level? I miss my voltage meter in my B5 S4

Enable battery meter on MMI through vcds.

[amusante]

Via MMI hidden menu or Vagcom.

I don't have a vag com so any help with the hidden menu would be great

[jl87]

You unfortunately need it for the hidden menu- sorry I didn't clarify. Here is the thread with the info you need if you can borrow someone's or your local shop has it.

http://www.audizine.com/forum/showth...ight=B8.5+VCDS

[APD]

car battery could be low too, when it goes into a low-power mode, the door sensors get shut off.

this

[jpfour]

If the trunk still works one of the door sensors has failed, they seem to suffer with water ingress. :-(

You need a vag com scan to identify which one has failed.

They are fairly fairly easy to replace there is a very good how to if you google "B8 door handle sensor replacement" the how to is for an A5 but ours is the same apart from the torque screw being under little plastic caps on the door edge.

[cjw]

Mine work perfectly every day, but twice this year, none of the handles worked. Ten minutes later, everything is back to normal and has been for weeks. Odd.

[amusante]

car battery could be low too, when it goes into a low-power mode, the door sensors get shut off.

So I'm thinking it is the car battery. When the car sits for a long time, none of the sensors work and I have to use the key to open and lock the car. If I have driven the car for a while, the lock and unlock sensors will work. I'm bringing the car in for a wheel bearing tomorrow, so I'll have them check the voltage too.

[will13k7]

So I'm thinking it is the car battery. When the car sits for a long time, none of the sensors work and I have to use the key to open and lock the car. If I have driven the car for a while, the lock and unlock sensors will work. I'm bringing the car in for a wheel bearing tomorrow, so I'll have them check the voltage too.

Sounds like what happened to me when my car battery was on it's way out.