Replacement Key Housing (Same Transponder)

[MadBlex]

Hello BimmerForums!

I purchased a 2001 740il about year ago and love it overall. It is my first BMW. I've also driven Lexus (ES, SC) in the past.

When I purchased it, the key definitely was aftermarket and the housing was kind of weak. I got a new key cut (it works on the door, trunk, turns the ignition, etc) after the old plastic cracked and broke. I put the transponder chip in the new key's housing from the old key. Now she won't start. I have done a lot of research but most key problems are when using an entire new transponder (lost key, etc). The only thing different is the metal and the plastic housing. The transponder chip is the same so I am not sure why she's not working.

If anyone has any advice or suggestions, I greatly appreciate it. Of course the local dealer quoted me $270.00 for an entire new key but since I have a working transponder, I don't feel like that is at all necessary.

Thanks in advance!

TLDR Put working transponder chip in new key housing with newly cut metal key and now she won't start. 2001 740IL

[MauiM3Mania]

Moved from the General BMW Discussion sub-forum.

I bet you get some help here!

[bmwdirtracer]

Welcome to the forum.


Take your registration and driver's license to the dealership and order a key. That is how you get a key for a BMW.

[dworthy]

Another options is to send it to this guy: www.bmwgm5.com

There is a good chance you have damaged the chip, but he will know for sure.

[danzee]

There are two security elements in the key. The obvious chip contains only one. The other is SMT mounted to the board as I recall, and it's the one married to the car and not owner re-programmable. The chip is owner re-programmable if you have another key. I think I wrote a step-by-step transplant post a long time ago. I'll see if I can find it. You will need to be comfortable with de-soldering and re-soldering a small SMT IC (chip). It's not for beginners.

[MadBlex]

Moved from the General BMW Discussion sub-forum.

I bet you get some help here!

Thank you! I will try to get a better understanding of the forum layout.

Welcome to the forum.

Take your registration and driver's license to the dealership and order a key. That is how you get a key for a BMW.

But I have a key, and a transponder chip that worked fine previously. It's not like I lost my key I just have a key that broke and got a new one cut that works fine on the trunk, door and turns the ignition.

Another options is to send it to this guy:www.bmwgm5.com

There is a good chance you have damaged the chip, but he will know for sure.

Thanks for the recommendation! The chip worked fine in one key so I am not sure how it could have been damaged but that might be a possibility.

There are two security elements in the key. The obvious chip contains only one. The other is SMT mounted to the board as I recall, and it's the one married to the car and not owner re-programmable. The chip is owner re-programmable if you have another key. I think I wrote a step-by-step transplant post a long time ago. I'll see if I can find it. You will need to be comfortable with de-soldering and re-soldering a small SMT IC (chip). It's not for beginners.

OK thanks! If you come across it please let me know.

Thank you all for your responses and recommendations!

[MadBlex]

Also - as a follow up. If I do have to go to a dealer, I read not to pay more than $150.00 or so. My local dealer quoting $270.00. Will a dealer mail a key if I can prove ownership electronically? If so, which BMW dealer offers the best price? $270.00 is steep for a key.

I am in Madison, WI if anyone has had a better local experience.

Thanks again everyone.

[dworthy]

Yes, and I would give these guys a try: www.thebmwminipartstore.com

I have heard in the past they will mail one as long as the address on your Drivers license and registration match.