Both keys' remote functions stopped working: lock, unlock, hatch

[iPhoneEngineer]

My '07 Z4 M Coupe's keys no longer unlock, lock, or pop the hatch when the buttons are pressed. This happened spontaneously; one day I go to lock the car, and it doesn't work no matter where around the car I hold the key. The keys have always had a somewhat short range, and on some occasions I'd need to try a couple times while moving the key around, but it's never been that big of a deal. Now, it absolutely never works regardless of where the keys are.

Any ideas for how this can be diagnosed, reset, or if it is a somewhat common problem? Thanks

[inTgr8r]

That's unusual that both keys stop working at the same time.
There is a reset procedure posted in here somewhere, I'm not sure it works if they're both bad though.

[gcochard]

My car did this the other day with one of the keys, I must have hit the button 20 times. I ended up locking it by putting the key in the door. It worked 4 hours later, hasn't had the problem since.

[iPhoneEngineer]

Interesting. Yeah, I've been locking and unlocking the car with the old-fashioned, easy-to-forget-about keyhole on the driver's side. I was also very surprised when I tried the second key and it didn't work either, which implies to me that it is something with the car and not the keys. I guess I could try disconnecting the battery, but don't really want to do reset my ECU adaptations if there is no reason to suspect that will help.

Is there a name by which this reset procedure goes? E.g. the name of the key communication system...

[iPhoneEngineer]

So across the web I saw a protocol that goes like this:

http://www.bmwtips.com/tipsntricks/P...s/ProgKeys.htm
Cliffs:
- Use the key to unlock the car (manually) and cycle the ignition on and off briefly
- Hold down unlock button, then tap lock button three times, then release unlock button

After doing this on both of my keys, neither of them perform the "confirmation" lock and unlock of the doors that is supposed to happen (I've even seen a YouTube video). This is frustratingly mysterious.

Any ideas? I haven't tried pulling the battery yet but am hesitant to go to the dealer, there must be something else to attempt...

[gferil]

Originally Posted by iPhoneEngineer

So across the web I saw a protocol that goes like this:

http://www.bmwtips.com/tipsntricks/P...s/ProgKeys.htm
Cliffs:
- Use the key to unlock the car (manually) and cycle the ignition on and off briefly
- Hold down unlock button, then tap lock button three times, then release unlock button

After doing this on both of my keys, neither of them perform the "confirmation" lock and unlock of the doors that is supposed to happen (I've even seen a YouTube video). This is frustratingly mysterious.

Any ideas? I haven't tried pulling the battery yet but am hesitant to go to the dealer, there must be something else to attempt...

This procedure worked for me, forgot where I got it from, but it worked on both my keys:

1. turn key to position 1 five times very quickly
2. remove key
3. Hold unlock button then press lock button 3 times, release unlock button. (The door locks should cycle to let you know it worked)
4. Repeat step 4 for other keys within 30 seconds to initialize them too.
5. turn on igntion to finalize

[ZStig]

your car doesn't want to let you back in. heh...

[dsgrillot]

Mine '06 Z4 did that...took the key to the dealership and they fixed it, no charge.

[iPhoneEngineer]

I reached a resolution late last week: the dealer was able to fix it, also for free (though I was visiting them with the claim that they broke my cupholder during installation of a new windshield, so they may have been more inclined to make it free than if I had gone in just for the key).

Most interestingly, the keys now have /significantly/ longer range than before. I don't see signs that they opened the keys to replace the battery, which I doubt they would do since it is relatively difficult/not intended service. Previously I had to be just feet from the car and they didn't always work on the first press anyway; now I can be a few car lengths away, easily.

I also realized that one possible cause was removing the mirror to send it in to radar-mirror.com for digital gauge installs. Perhaps the antenna or other electronics to process the wireless signal are located there, and the reason for the better range is related to modifications performed inside the mirror to fit the other electronics...

Anyway, in short, if both of your keys stop working at the same time it's almost certainly not just the keys' problem and an expensive new key probably won't do you any good, so don't be afraid to bring it to the dealer (with BOTH keys in-hand).

[elerner61]

I'm curious about the Remote-Mirror setup you did. Where are you mounting (concealing) the main unit?

[gcochard]

If I'm not mistaken, he just got an AEM gauge installed there, no radar detector.

[iPhoneEngineer]

Originally Posted by cliffhopper

If I'm not mistaken, he just got an AEM gauge installed there, no radar detector.

My mirror has two AEM digital gauges in it (boost and AFR), as well as the Beltronics STiR+ radar detector display. None of it is hooked up yet as I haven't had the time. Accordingly, I really have no idea where anything is going to be mounted . If anyone can point me to similar Z4 installs, I'd be interested.

I'm still really impressed and pleased by the extra range/reliability of the key's remote functionality. Used to hate it when it was so unpredictable if I could get the passenger side unlocked for someone else, bending down to see if the lock actually popped up!

[gcochard]

http://www.billswebspace.com/bmwmc.htm has a valentine 1 hardwire install in a coupe. Not really sure if you need it to be there though.

I would maybe stick it on the top of the bulkhead between the seats and the trunk. You can build a nice leather enclosure for it if you want to conceal it.

[iPhoneEngineer]

Originally Posted by cliffhopper

http://www.billswebspace.com/bmwmc.htm has a valentine 1 hardwire install in a coupe. Not really sure if you need it to be there though.

I would maybe stick it on the top of the bulkhead between the seats and the trunk. You can build a nice leather enclosure for it if you want to conceal it.

Cool, nice reference--I used Bill's header install guide but haven't checked out enough of his other articles.

I thought it was pretty nuts that with the recommended front-installed sensor you can't detect a rear radar hit (obviously the engine block, radiator, intercooler all shield the signal), so I would definitely like to investigate an interior mounting with view of both the front and rear--probably off-center a bit so it doesn't appear in the rear view mirror.

[gcochard]

You can stick it behind the passenger seat, but it'd probably be blocked from the front when you have a passenger.

Maybe inside/instead of the sunglass holder?