Use toothbruh charger to charge BMW key

[scirocco]

I just cut a hole in a peice of styrofoam so it went around the protrusion of the toothbrush charger to give it a larger flat surface. THen stuck two pieces of small styrofoam blocks on this round donut shaped piece so that the key fob was supported on either side while sitting vertical.

[Jungerishere]

Originally Posted by rayxi

I can say for sure that it works on my E46 as I have recharged a dead key that way. It may not work on other models like the E53 however. I don't have my E53 anymore so I can't test it.

Yup, I have charged the key on position 0 many times as well on E46. I have three keys and don’t drive the M3 much so I let the keys charge in the ignition. However, I noticed that you need to switch to position 1 or 2 first and then back to 0 and leave the key in for it to charge. If you just insert the key and leave it in position 0, key does not charge. I let it charge for several days and the keys are good to go.

I have also tried with Qi charging pad and the key does not charge. I guess the key doesn’t meet Qi standards. All of my charging pads have charging LED indicator when Qi receiver (my phone) is placed on top to notify you that the device is charging. Placing the key on the pad doesn’t do this. Tried many different placement on the pad and the key still does not charge.

Here is a link with the toothbrush changer and this guy in the video was successful in charging the BMW keys. Video shows Philips Sonicare rechargeable toothbrush base. Maybe I’ll pick one of these up and try it out. But currently, all of my keys are charged and working…

https://www.youtube.com/watch?v=kC68Z7CP2XM

[Qsilver7]

I'm scratching my head on the car charging the key when the ignition is off. My question is...how is any induction charging going on when there's no power? It would be like using your toothbrush induction charger...but not plugging it in...again,how is there any induction going on? But if you say it worked...I'll have to take you at your word....but I'm still scratching my head.

BTW...it can take up to 30 hours to recharge a completely depleted remote key

The e46/e38/e39/e52/e53 are all of the same generation BMWs and uses the same systems...so the new style key (9/99-up build date)...has the same basic design. The key blade changed in later years....but the internal working of the key remained the same:

KL R=ignition position 1

[Jungerishere]

Originally Posted by Qsilver7

I'm scratching my head on the car charging the key when the ignition is off. My question is...how is any induction charging going on when there's no power? It would be like using your toothbrush induction charger...but not plugging it in...again,how is there any induction going on? But if you say it worked...I'll have to take you at your word....but I'm still scratching my head.

It worked for me. As mentioned, I have three set of keys for E46. I purchased the third key thinking my original two keys had bad batteries. I read a thread somewhere that the key can be charged by leaving it in the ignition for few days so I left the key in at position 0 and it started to work after few days. As mentioned before, I needed to switch to position 1 or 2 first and then back to 0 and leave the key in for it to charge. I found this out when I tried to charge my second key since the second key didn't charge after few days. Thinking that I didn't insert the key all the way in, I turned the ignition the position 1 to test and then back. Left it for few days and the second key worked. Two original keys are charged and works fine. I don't drive the M3 during winter seasons and sometimes long stretch of times so I've been alternating keys in the ignition to charge the keys. I've done this for many years and all three keys still works.

[Doru]

Originally Posted by scirocco

I just cut a hole in a peice of styrofoam so it went around the protrusion of the toothbrush charger to give it a larger flat surface. THen stuck two pieces of small styrofoam blocks on this round donut shaped piece so that the key fob was supported on either side while sitting vertical.

Why don't you take a quick pic with the cell phone and post it here?
You know what they say: "a picture is worth 1,000 words"

[Qsilver7]

Originally Posted by Jungerishere

It worked for me. As mentioned, I have three set of keys for E46.

Don't take my previous comments the wrong way...as I said...I take you at your word that it works...but that doesn't stop my inquisitive nature and wonderment as to "how" it works.

Another suggestion for those with multiple remotes that don't get used a lot...if you have a battery charger, float charger, of battery tender that you can plug into a wall outlet...you can hook it to the engine bay jump terminals, then insert the remote key into the ignition and leave it in position 1 over night...or for the prerequisite 30 hours...boom...the remote key should be recharged for a good year or more....without running the battery down or having to drive around town tryig to charge the remote key up.

If all you have is a full size battery charger...if it has multiple settings...use the lowest setting like 2 amp or 6 amp etc...you don't want to overcharge your car battery.

[StirFriedPanda]

I couldn't get my Qi wireless charger to charge my key fob. But the toothbrush charger worked great (after having to re-program it)!