[Nickco43]

If your having any problems with your keys this guide might prevent you from spending $500 at the dealership which is insane for a $10-$50 key fob.

My key case looks like crap?

You can buy aftermarket case replacements for both CA and non-CA keys. Every single key I own has an aftermarket case and the only difference is that OEM keys are glued together while the aftermarket cases are snap together. Fit and finish is the same.

CA
Non-CA

Take a razor blade and cut open around the side of the case. Once the key is open then take the PCB and place it in the new case. Only use a razor blade and wear gloves. I have two deep gouges in my hand from opening up key fobs. Do not use a kitchen knife or screw driver.

Here is a video showing the process:

My CA car shows that my key battery is low?

CA keys have a user replaceable CR2032 battery. Remove the metal key and pry open on the little battery hatch and replace the battery. It is very simple and takes less than 30 seconds. No need to go to the dealer.
CR2032 Battery

My Non-CA key will start my car but not unlock/lock the car doors?

Your battery is either dead or low. Non-CA fobs have a soldered on battery that gets recharged by a coil in the key slot. BMW says this battery will last the lifetime of the car. This, like their 15,000 mile oil change and lifetime trans fluid claims is not true. You can try going on a long drive in the car to charge the battery or place the fob overnight on an electric toothbrush holder. If you don't use the fob that often then one of those methods will most likely work.

(Note: The BMW diamond key from a previous generation BMW is shown. These have the exact same charging electronics as our cars)

If charging does not work then you have to have the battery replaced through a third party. Solder on replacement batteries are available if you have soldering skills or PM me if you need your battery swapped.


ML2020 Battery

If your fob is still not working see if the battery has close to 3v. If it has 3v then go to any auto parts store and use their RF tester to see if the remote is sending out a signal.

Also your 15 amp door lock fuse my be blown.

My key got wet?

Immediately put your key in silica gel or rice. If you are lucky the rice or silica gel will absorb any moisture that got into the key and it will continue to function. Some times the key will continue to function for a week or a month and then die.

If your key is dead after drying out you have three options:

1. You can send out your key and have the logic chip micro soldered onto a new key. (PM me for a logic chip swap.)
2. You can have a locksmith program you a new aftermarket key ($100 to $300)
3. You can go to the dealer and have them program a new key ($300 to $500)

My CA key will unlock/lock the doors using CA but will not unlock/lock the doors with the remote?

You key is out of sync with the car. Take your key and use the slot to start the car. After 30 seconds your key should be resynced with the car and your remote should work.

My CA key will not allow me to unlock/lock the doors or start the car with CA?

Try replacing the battery in the fob. If that doesn’t work then try resyncing the door handles.

1. Insert the metal key into door lock to manually lock and then unlock the doors.
2. Insert the CA fob into the slot and then start the car.
3. Turn off the car and remove the fob.
4. Lock the door with fob button.
5. The door handle CA should work again.

If those two failed then it could be a whole bunch of electrical related issues. Scan the car with INPA.


My one button on my fob is not working?

Go to an auto parts store and use their IR tester to see if your other buttons are sending an IR signal. If the key is sending out a signal then you need to have that button replaced. If it is not sending an IR signal at all then you need a logic chip swap. Send me a PM.

My key is lost?

1. You can program a key yourself with a special tool.
2. You can have a locksmith program you a new aftermarket key ($100 to $300).
3. You can go to the dealer and have them program a new key ($300 to $500).

Replace the battery. If that doesn’t work then your button is damaged and will need to be repaired. Send me a PM.

If your key issue if not listed above then make reply to this post.

List of Locksmiths:

Disclaimer: I and/or E90 post are not affiliated with any of the mentioned locksmiths. These people have been mentioned to do good work by various forum members. It is up to you to make sure a qualified individual works on your vehicle. I would avoid cash only operations and only pay using a Goods and Services PayPal. Ask if they have any type of insurance if something does go wrong with your CAS module. That being said I will do board repair work on our keys on a case by case basis. Send me a PM if interested.

• G Coding in Slidell, Louisiana. Cell: +1 (985) 492-0666 Email: GcodingBMW@gmail.com
• Ishmael(The guy in that50'skid video) in Irvine, CA. Cell: +1 (949) 491-3422

Sticky me

[BimmerNugget]

wow! Thanks man! Very helpful and informative. Everybody on here talks about mods and oil leaks all day but I don't think there's much info out there about these mysterious BMW keys.

[Nickco43]

Originally Posted by BimmerNugget

wow! Thanks man! Very helpful and informative. Everybody on here talks about mods and oil leaks all day but I don't think there's much info out there about these mysterious BMW keys.

My testing with the keys is almost done. I wouldn't feel right if I didn't share all of my information I found out along the way. Keep in mind all of this was out there scatared between the 1,3,5,7,X model fourms that use the same key.

I think it would be a huge benefit to the fourm if we compiled a list of third party locksmiths who will program new keys for our cars. Not all locksmiths will make BMW keys and a few say they will do it and end up killing the CAS module.

If anyone has used a locksmith before to have a keyed made, PM me his name and contact info and I will add it to the original post.

[gamesfrager]

Nice list. I would say be very careful getting the cutter blade too far inside the housing. You don't want to damage any of the components.

I saw this a while back

Skip to 12:50 in the video

[Nickco43]

Originally Posted by gamesfrager

Nice list. I would say be very careful getting the cutter blade too far inside the housing. You don't want to damage any of the components.

I saw this a while back

Skip to 12:50 in the video

That is the video that sparked my entire project. I know the guy in the video makes e90 keys and will be added to the list of locksmiths.

[tlow98]

Nice! Someone needs to sticky this!

[Nateom3]

I can cut and Program BMW key fobs if any one needs help. Will one working fob or all keys lost.

[shaithis]

One of my fobs does starts the car but no remote functions work, I opened it to check the battery voltage which tested at 3v.

Looking at the board shows some damage on/near what I believe is the transponder chip....do you think this is repairable? I have attached a screenshot

[Nickco43]

Originally Posted by shaithis

One of my fobs does starts the car but no remote functions work, I opened it to check the battery voltage which tested at 3v.

Looking at the board shows some damage on/near what I believe is the transponder chip....do you think this is repairable? I have attached a screenshot

It looks like the IR blaster chip got wet. If you had someone solder the larger chip from your key onto a donor board it should work.

[Emilime75]

Originally Posted by shaithis

One of my fobs does starts the car but no remote functions work, I opened it to check the battery voltage which tested at 3v.

Looking at the board shows some damage on/near what I believe is the transponder chip....do you think this is repairable? I have attached a screenshot

If it were me, I'd take a q-tip and some De-Oxit electronics cleaner, and clean all of the corrosion on the board. That, in itself, might get it working again.

[335ivin]

Nickco43

Is the ML2020 Battery the correct battery for the NON-CA key fob?

[Nickco43]

Originally Posted by 335ivin

Nickco43

Is the ML2020 Battery the correct battery for the NON-CA key fob?

Correct, Make sure you buy a battery with the pins clocked correctly.

[delmarco]

Originally Posted by Nickco43

My Non-CA key will start my car but not unlock/lock the car doors?

Your battery is either dead or low.

This is a awesome thread but this particular case where your BMW keyfob starts your car but does NOT unlock/lock your car is NOT ALWAYS because the keyfob battery is dead.

There is a 15 AMP "remote door lock/unlock" fuse that can be blown and will cause this particular issue.

Unplugging the car's battery and replacing the blown fuse (possibly also upgrading the blown 15 amp fuse with a healthy 20 amp fuse) usually fixes this problem if indeed you find that there is a blown fuse in that slot.








I just discovered this issue in my car and replacing a blown fuse first is a quick and cheap solution before attempting replacing the keyfob battery or the key:

[Nickco43]

Originally Posted by delmarco

This is a awesome thread but this particular case where your BMW keyfob starts your car but does NOT unlock/lock your car is NOT ALWAYS because the keyfob battery is dead.

There is a 15 AMP "remote door lock/unlock" fuse that can be blown and will cause this particular issue.

Unplugging the car's battery and replacing the blown fuse (possibly also upgrading the blown 15 amp fuse with a healthy 20 amp fuse) usually fixes this problem if indeed you find that there is a blown fuse in that slot.








I just discovered this issue in my car and replacing a blown fuse first is a quick and cheap solution before attempting replacing the keyfob battery or the key:

I will add this fix to the guide.

[delmarco]

One other thing I didn't think of when your Key Fob isn't working but your central locking button and door actuator and door actuator fuses are all fine. FUSE 63 needs to be checked.

[e90yyc]

Nice guide!

One suggestion: I believe “IR tester” s/b “RF tester,” ya?

[Nickco43]

Originally Posted by e90yyc

Nice guide!

One suggestion: I believe “IR tester” s/b “RF tester,” ya?

Fixed.

[bsmoov]

I have a very, very, very, unique key situation.

I recently purchased a car and only have 1 key.

Key starts the car in the key slot via push start

Key does not unlock doors via remote

Key does unlock doors via manual key blade

All fuses are good

Central locking from the interior buttons work

Here is the kicker: The key fob is a Comfort Access key fob with the removable battery, but the vehicle is NOT equipped with Comfort Access. I checked the car and the car's door handle for the Comfort Access stuff and it definitely does NOT have comfort access.

I'm guessing the previous owner took the key blade out and inserted into the wrong key holder? But the pcb is in the key holder, right? How can the car start via the push button/key slot if it is indeed the wrong key holder?

What to do? Would a new key work?

[Nickco43]

Originally Posted by bsmoov

I have a very, very, very, unique key situation.

I recently purchased a car and only have 1 key.

Key starts the car in the key slot via push start

Key does not unlock doors via remote

Key does unlock doors via manual key blade

All fuses are good

Central locking from the interior buttons work

Here is the kicker: The key fob is a Comfort Access key fob with the removable battery, but the vehicle is NOT equipped with Comfort Access. I checked the car and the car's door handle for the Comfort Access stuff and it definitely does NOT have comfort access.

I'm guessing the previous owner took the key blade out and inserted into the wrong key holder? But the pcb is in the key holder, right? How can the car start via the push button/key slot if it is indeed the wrong key holder?

What to do? Would a new key work?

It is probably an aftermarket key that does not have the frequency set correctly.

[bsmoov]

Originally Posted by Nickco43

It is probably an aftermarket key that does not have the frequency set correctly.

So if I order a new OEM key, everything should work?


So previous owner bought an aftermarket case and swapped the guts, chip works for starting car, but buttons don't work due to incorrect frequency?

[Nickco43]

Originally Posted by bsmoov

So if I order a new OEM key, everything should work?


So previous owner bought an aftermarket case and swapped the guts, chip works for starting car, but buttons don't work due to incorrect frequency?

Possibly, take a picture of the pcb.

[fleet]

Key problem? I accidentally left my fob in the dash last time I moved my e91. Over the following few months, the car's (new in December) battery ran down to nothing. I had to attach a jump box to the under-hood jump spots to power up the car to remove the key. Car battery is now charged, key fob seems like it has a charge (it locks and unlocks car) but seems to be no longer recognized by the car for operation- I cannot start it, or even power it up in the accessory position.
(Non-CA, 2007 328xi)

Edited to add: I do have the ELV symbol on the cluster. Will this prevent the ignition from even going into "accessory" (pressing start/stop with no foot on brake)?