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Yes. The BMW keys charge in the car by induction charging just like the newer phones do.
 

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bought a $10 wireless charger meant for smartwatch, will give it a go. Maybe it'll bring one of my dead keys back to life...
 

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If the Battery tender is hooked up and key is turned to 2nd position car battery won't die right?…just wanted to give this a shot, as I can't see car pulling much power if fans and lights are off with this idea.
Apples
I wouldn't recommend this. I tried with my car plugged into the BMW trickle charger and it killed my battery. No DLRs, radio off, HVAC off, etc. I want to make sure someone else doesn't make the same mistake.
 

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bought a $10 wireless charger meant for smartwatch, will give it a go. Maybe it'll bring one of my dead keys back to life...
I use the inductive charger for my electric toothbrush. Second owner since early 2003, still on original master keys!

Regards,
Jerry
 

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Any idea what wattage the toothbrush charger is? Ive heard a lot of people using them, probably because they are very low wattage compared to all the phone chargers.
 

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Any idea what wattage the toothbrush charger is? Ive heard a lot of people using them, probably because they are very low wattage compared to all the phone chargers.
Best I can do is share the brand. It is a Phillips Sonicare. Maybe 5-8 years old. I am guessing it is a pretty standard charger.

Regards,
Jerry
 

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Best I can do is share the brand. It is a Phillips Sonicare. Maybe 5-8 years old. I am guessing it is a pretty standard charger.

Regards,
Jerry
I use the same. The precise model of the toothbrush is HX5000 and the charger is HX5100. No issues. It's rated for 0.9/1.1 watt.
 

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I ordered a spare sonicare base (1.5W) and my key has been sitting on it for a day now. Still not working. I'll let it sit more before giving up.
 

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I ordered a spare sonicare base (1.5W) and my key has been sitting on it for a day now. Still not working. I'll let it sit more before giving up.
So I am trying to remember. The key also charges in the ignition wirelessly. There is an induction ring that allows the charge. Given that neither the car ignition or the induction charger is working, perhaps there is something wrong with the induction ring or its connection?

Maybe google YouTube for someone repairing the induction ring on a BMW key? A bit of a longshot, but otherwise, I am guessing about $150-$200 at the dealer to replace.

Regards,
Jerry
 

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I wouldn't recommend this. I tried with my car plugged into the BMW trickle charger and it killed my battery. No DLRs, radio off, HVAC off, etc. I want to make sure someone else doesn't make the same mistake.
Yeah all the electronics and things like throttle stepper motors actually draw a TON of current just being 'on.' Much wiser to just try using the key while driving around rather than letting it sit with the car on for a long period of time, even with a higher current charger hooked up, still not a good idea for any length of time!

As for dead keys themselves that don't seem to charge up anymore, I think it's possible to replace just the battery in there; might be worth attempting before shelling out for a whole new key!
 

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FWIW, I tried to wireless charge my keys on a sonicare charger that I had, then some cell phone chargers and it all didn't work. I sent my 2 keys (1 at a time, b/c I didn't have spares) to Scott at BMW General Module 5 (GMV, ZKE V) and he opened them up and swapped batteries for $50 a pop. Was about 1 week turnaround (shipping was the big time-suck). It's been 3 years and the keys still work great - I just keep on rotating them to make sure they don't die.
 

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My problem has always been drive time. While my car is my DD, my commute is only a few miles and takes 6 mins to get to work. So the key probably doesnt get charged in the ignition long enough. But I do find it odd that the key that I got the car with lasted many years, and this new one lasted less than 2 years with no real change to the daily routine. But now with quarantine, the car has been sitting and not getting driven. Its on a trickle charger but the key is dead.

I might look into a battery replacement since 1-2 weeks without it wont affect anything.
 

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I just sent off my key to bmwgm5 (linked above) who told me that he very rarely replaces batteries on these fobs. Its 99.999% of the time something wrong with the circuit board due to vibrations and such. He said that the battery would not drain even if left in a drawer for 10+ years, so I just sent it off and should get it back in a week or less. I'll report back once its returned.
 
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