Tesla1856

So, what was the end-resulting fix?

Wife was telling me her 2020 Q5-e Fob-1 has been having problems detecting.
Now today, my Fob-2 would not detect either (in my jeans-pants pocket),
... but WOULD connect when placed a little closer in console-pocket near gear-shift.

Guess I'll try new batteries in both Fobs. I came here to find-out if these batteries really only last a year-or-so.

@AT

In my previous 2016 Allroad and 2018 Q5 my battery lasts about a year of almost daily using the vehicle. However, your car should notify you when battery in the FOB is almost discharged (Yellow key on dashboard).
CR2032 is the battery in the FOB.

MH62

I'm pretty sure the battery is for locking/unlocking the car and the key recognition uses an RFID chip which isn't powered by the battery. In theory, you should be able to remove the mechanical key from the Fob, leave the rest behind, go to your car, mechanically unlock it and start it. So if detection is failing, it would have to be related to the RFID transceiver in the car or the RFID chip on the key.

@AT

Unfortunately, this is fully correct statement . In simple words - Advances key can communicate with car immobilizer in 2 ways:

• when it detects request from immobilizer it sends response using transmitter powered by key battery
• when buttery level is weak or no battery in the advanced key it should be placed in designated place (like example in driver side cupholder in in Q5 MY2018-2020 center console). In this immobilizer fob component in the advanced key get power wirelessly (the similar way as RFID)

OFDPOS

I'd have to dig out the paperwork on what they replaced on our 2018 Q5 when it was happening with that one.
First they said it was the battery in the key fob , several batteries replaced and still doing it. Next it was the key fob,. several at least 3 different ones and it still did it.
Then they replaced some control module ? and that still didn't fix it they bought the vehicle back.

Now here we are with a 2021 Q5 and doing the same thing .
Latest ;
Yesterday morning wife goes to leave for work, opens the door and it lights up in the MMi screen user and it has my name NOT her's , she tries to start vehicle center dash lights up Remote control key:
hold back of key against the designated area. See owner's manual.

So she puts the key in the spot , pushes button to start here's a little click click noise from inside the car NOT the starter trying to engage !
Then all the lights in the dash light up , but car will not start . She gets out of the vehicle with key fob in hand walks in the house comes back out and tries to it again same thing even with putting key in the spot.

Frustrated she comes back in grabs my key fob and goes out it starts and left for work.

I call the SD and the soonest they can get the vehicle in is Sept 1st.

Now had she been anywhere else , she would have been stranded till either I showed up with the other key fob or call roadside assistance and have them tow the vehicle to the dealer .

Looks like it's time to get Audi America involved once again.

Before someone says just have her keep your key fob or switch . That's ridiculous to pay this kind of money for a vehicle and have this kind of problem and have to carry both key fobs...

anak_ur

My 2021 Q7 has the exact same problem. It’s only 6 months old and this is the main issue because I won’t start on both of my key fobs. I have an appointment to get this fixed on Sep 8. But now we cannot use this car. It’s really ridiculous! Please let me know when you know what’s wrong and how they fix it! Thank you in advance!

OFDPOS

SW just called , Audi wants to try and replace the Fob. And in their words do to the chip shortage they have no idea when the Fob will show up.

Tesla1856

Just reporting back. New batteries in both Fobs seems to have fixed the "short range" issue for us.
My notes:
Both of the Fobs for our Q5-e seem to have short range, all of a sudden.
Hers did not work from purse, once. Mine did not work from my jeans pocket once.

Replaced both with Duracell Alkaline CR2032-3v
- Voltage when new 3.25 volts.

Old batteries were both 2.99 volts (with voltmeter, but with "no load on it" of course).
I kinda doubt voltage under the load of running the fob is near that.
Easy to replace. Did both. Did not have to re-program/re-link.

I wonder if fobs being only about 15ft away from vehicle (inside on counter) makes a difference
(like it ends up being close, so maybe always generating new fresh codes to un-lock car if needed)

OFDPOS

I'm glad that fixed your problem !

It's not a short range problem, It's a fob/ vehicle problem fon ours.
When you can hold the fob in your hand sitting in the vehicle and on the dash it reads doesn't recognize key fob hold back of key fob against the designated area. See owner's manual. And nothing will not start !

They are saying do to the "chip" shortage they are having a problem getting a new key Fob !

Maybe the in the know crowd here can verify this, but according to them (Audi dealer) each key fob is dedicated to each individual vehicle's vin # .

Last time I dropped off the vehicle I asked the tech about how far away from the vehicle can I stand/place the fob and the vehicle won't as you said refresh codes and he said after you are 8-10 feet away it won't communicate with the fob.

Tesla1856

1. Yeah, sounds like "not battery" in your case.
2. I did read that some new Audis might just come with one FOB now, and you get the other one later.
3. Not sure what that means. Obviously, you can lose one. It can then be "de-registered" and you can get a new one to replace it.
4. I could even call it 10-ft (just not sure where sensor is in the car).