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edd_jedi

Key Fob Remote Sync

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2005 E61. My car came with two keys (the older diamond shape type) but only one of them opens the car remotely. The dead one does start the ignition so I believe it is correct for the car. I recently had the rechargeable battery replaced in the dead one, and used it for a good few hours over the weekend to charge it, but it still doesn't work.

 

I have tried the attached process for pairing the key, but I also can't get it to work. In fact the process doesn't even work for the good key which does remotely lock the car. I have heard people say it could be the diversity antenna, but that seems unlikely as both the (working) remote key and radio reception work fine. I have also been told by somebody else that E60 keys do not need pairing, only older cars like the E39/E46 do, but I don't know if that's true, they could be referring to the later E60 keys which slot in.

 

Does anybody have any ideas how I can get this key working? Is it likely anything other than the battery is at fault? As above my only problem with this theory is that I can't get the sync process to work with the good key either.

key.jpg

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It looks to me like you have got everything covered. The only think I could add is that using the diagnostics it is possible to disable or enable a specific key. Perhaps your additional key has been disabled at some point because it was considered lost? The thing is, is that if that was the case I don't think it would start the car either.

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Here's what you can do.....

Most likely a component on the key circuit board has failed. The keys essentially have two components inside: 1 is the ignition transponder chip, highlighted in red below pic of older E39 remote. 2 is the central locking circuit board. If you opened up the "broken" key and removed the circuit board it will behave the same way (start the car) so long as the transponder is still there for the ignition to read it. The transponder chip is not attached to the circuit board.

You can buy a second hand key and use the central locking circuit board from it in your key and use the above method to sync it to your car. I have done this with my old E39. Be sure to use your original transponder, and bin the one from the new bought key. It is useless and cannot be trained to any other car than it's original AFAIK. Image result for e46 transponder key

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On 25/11/2018 at 13:39, edd_jedi said:

In fact the process doesn't even work for the good key which does remotely lock the car.

Can you explain this? The working key does or does not open/lock the car remotely?

Edited by keliuss

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2 minutes ago, edd_jedi said:

Yes it does open the car remotely, but from what I have read the above sync process should work for this 'good' key, it does not.

So what's not synced/working about the good key, if it's working fine?

Anyway, to answer your question: Yes, the syncing process works. I bought a second hand E39 key from fleabay and used it's circuit board in my original key with my original transponder and the process worked. It remotely locked/unlocked my car. It was maybe 8 years ago so I cannot remember if the above method is the one I used but I just googled it at the time and it looks the same to me.

Keliuss

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OK, I'm assuming you are not getting a confirmation (step 5) that the process is complete. My memory for details doesn't go back that far I'm afraid. All I know is I used a method found on the internet and it worked. My car was a 1997 E39 and used the rounded shape key pictured at the top in the method posted above.

Keliuss

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I'm trying to find out if this process works with the E60, I know it works with the E39. My understanding is you cannot just sync one key, you need to do both at the same time, hence starting with the working key.

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Thought I'd have another go at this now that I have ISTA. I checked the key information, and it turns out the working key I have is #3, and the one that starts the engine but won't work remotely is key #2. So key #1 must have been lost by a previous owner. Both keys are 'enabled' according to ISTA. I tried enabling key #2 again, but remote locking still doesn't work.

 

Could the fact I am missing key #1 explain why I can't get the remote initialisation to work? But surely it must be possible to enable extra keys if you lose #1?

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Just in case anybody finds this old thread in a search I thought I should update it with the solution! So having had no luck synchronising the key, I decided to open it up to test the battery (which had already been replaced by the previous owner.) When I opened the key, I found that the positive connector on the battery had broken off, so it wasn't even connected to the PCB! :D

 

I tested it with my multimeter and it was completely dead reading 0v, not surprising after nearly 5 years. Rather than try and revive it I bought a new battery, case and blade kit, which only cost £6 on eBay. The old case was in very bad condition having already been cut open and glued back together, and I found a local auto locksmith who cut the blade for £9.

 

I soldered on the new battery, but it still wouldn't lock or unlock the car. I tested the new battery with my multimeter and it read just 0.1v, well below the 3v required to operate. I tried charging it overnight on my toothbrush charger, but that didn't do anything. Over the next few days I used this key for my journeys, and after roughly 4 hours of driving the battery charged up to 2.8v, at which point it started working again!

 

The final result is pictured below, a working remote key with new battery and a nice new case/blade that cost me under £15 in total. I have ordered a new genuine BMW badge from Cotswold for £5, just waiting for that to arrive.

 

So a few myths debunked and some useful information:

  1. Diamond keys do not need initialising in the E60, this process only seems to be applicable to older cars such as the E39 and E46. Instead you can use ISTA to check if the key is 'enabled'
  2. Electric toothbrush chargers do not charge key batteries. Well my Philips one doesn't anyway
  3. It takes a lot longer than the widely mentioned 45 minutes of driving to charge a flat key to a useable level, it took more like four hours
  4. When you buy a new rechargeable battery, it may arrive flat and require significant charging before working
  5. The replacement aftermarket key case clips together, so no cutting required in future should the battery ever need replacing again

I hope this helps, if your old key no longer works remotely or even just looks tatty I highly recommend this repair, under £20 all in instead of £150+ the dealer would charge for a new key :)

 

IMG_1468.thumb.jpeg.4092a8b1d65d4672db9e01b78251bbe1.jpeg

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Good result in the end 8-)

As I have said in your other post on this matter, it takes 30hrs to fully charge up your key fob

& the induction phone "wireless" chargers are supposed to be very good for this :-)

People who do this on a regular basis have reported much greater distance (locking & unlocking)

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I don't have a Qi charger, but my toothbrush charger didn't work. The key does have an inductive coil inside it, but I don't think these things are universal. I'm pretty sure Qi chargers have something inside them that 'activates' the charging, they don't constantly kick out a charge in the hope something is nearby. I have also read a lot of tales of people charging keys using things other than the car itself, but I've yet to see any actual evidence.

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