Comfort Access / Key Issue

[djrafacz]

Hi,

I am having an issue that I can't figure out and would like to see if anyone else has some insight into this. A couple of days ago, I opened my car like normal and went to go pick up some food. I arrived at the location, and exited the car and went to lock the door with comfort access, nothing happened. I saw inside that a message was on the screen that the key is missing (usually a normal thing as I'm not inside the car). I thought it was just a temperamental thing and once the car fell asleep maybe it would reset itself. It did not. These are the troubleshooting steps that I have tried so far.

1. Let the car go to sleep and try again in a couple of hours. No change.
2. Replace key batteries. Tried 2 new batteries and 2 used but good batteries. No change.
3. Hold key to the lock cylinder for 1 minute when starting. No change.
4. Checked all fuses related to locking via the fuse diagram paper. Trunk fuse panel, BCD fuses, and front passenger side panel. All fuses are good. No change.
5. Disconnected the battery for 1 hour. No change.
6. BimmerLink scan on the car. 2 codes were in the BCD will list below. Cleared codes. No change.
7. Dissected the key fob. Battery making good contact, roughly tested for shorts, could not find anything. Board was clean, no water ingress, components looked clean, radio antenna in key has continuity. Left the battery out for a little bit as well. No change.
8. Disconnecting and reconnecting the radio transmitter in the trunk panel. No change.

- I only have 1 key for this car.
- I never got a message that the key battery was on its way out.
- Car battery is about 1 year old with good voltage.
- I can only start the car by holding the key to the steering column, so both interior and exterior sensors / antennas are not working.

These are the codes I received when scanning the BDC.
8044D7 - Interior light layering LIN: Number of layering slaves incorrect
D90D01 - Transmitter-receiver radio (1. FBD II) (LIN): Missing LIN slave

Through my research, there are no fixes that have been posted other than one person saying disconnecting the radio receiver in the trunk and plugging it back in fixed their problem. Their problem also included a TPMS error, where the car would not read the PSI from the TPMS sensors. My sensors are functioning correctly without issue (PSI, Temperature, etc.)

The next steps I am thinking is to purchase a used ($20-40) "Radio remote control receiver" to see if the receiver is the issue.
Part numbers: 61359374504 or 61359319081 or 61359397846 or 61356806871 or 61356844138 or 61358802918 or 61358706502

If that does not work, I am not sure what else I can test to see what could have went wrong. I appreciate any feedback as I would prefer not to unload the parts cannon on this issue as it could get costly with 6 different CA antennas plus the receiver module and a new key.

[stocktree]

Perhaps order another key, since you only have one

[djrafacz]

Update

It was indeed the key. I tried out the OTOFIX IM1 key fob programmer and bought 2 cheap keys off of eBay and programmed both. Started working straight away.

The Lin BUS failure was a missing fuse for the exhaust flap.

[Qsilver7]

Originally Posted by djrafacz

Update

It was indeed the key. I tried out the OTOFIX IM1 key fob programmer and bought 2 cheap keys off of eBay and programmed both. Started working straight away.

The Lin BUS failure was a missing fuse for the exhaust flap.

Just curious…was this less expensive and less time consuming than giving a BMW dealership your VIN and proof of ownership, then ordering the remote which comes already programmed with your BMW’s encryption?

Using the VIN of my 2014 X5…you can see the part number & cost of a replacement remote based on how it’s optioned…how does it compare to what you had to pay for the programmer and blank key fobs?

[djrafacz]

I'm more of a DIY person so it was worth it to me. I made a key for my girlfriends F30 as well. So based on your screenshot it most likely would be 900 for 3 keys which is about what it cost me to make them myself minus the cutting of the blade.

300 would get you the key, if it fills key slots that render your comfort access for that key disabled, I think BMW charges a "programming" fee so it could definitely cost more.

To each their own though, there are definitely risks with programming on your own. BDC cars with that programmer are through OBD so it was like 20 minutes to make 2 keys.

[Qsilver7]

Thanks for the additional info.

In regard to the “programming” by the dealer…its a good additional money maker for the dealership…since many owners may not need the “programming”.

Since the remotes come already with the 128-bit encryption when ordered from BMW, and if you purchase the metal key, that will come already cut to fit the lock cylinders. The ”programming” the dealers sell (without really explaining it) is used to disable any missing/lost key from operating the vehicle. So if you lost the remote fob in a place where it could never be tracked to the vehicle…then the extra programming isn’t really needed unless you want to do it for peace of mind. If the BMW has comfort access…the programming will prevent the lost remote from being able to not only start the vehicle, but also prevent it from unlocking the doors (with the CA feature). So even if they used the metal keyblade to unlock the driver’s door, the remote won’t be able to start the vehicle or unlock the vehicle using CA when it has been disabled through programming.

Glad to hear/read that you were able to get done what you needed. There’s usually not that many success stories with the new generation remotes.

BTW, if anyone is curious as to what a new remote can go for…first use your VIN on a parts database site like realoem.com or bimmercat.com to get the correct 11 digit BMW part number for the remote or key that your BMW uses. You can then go to the BMW Mini Part Store site and paste the correct 11 digit BMW part number into the search box to find the exact type of remote/key you need and see how much the MSRP is and how much of a discount you may be able to get.

[djrafacz]

Is it correct that most FEM and BDC cars have a limit of 2 Comfort Access Keys that can be used? For example if you have 2 active keys then the new 3rd or 4th key is the one that will not have any Comfort Access features until one from slots 1 or 2 is disabled. I did not test mine out as when I was programming my keys I disabled the lost keys anyways.

Sometimes it is not just for peace of mind as you described. If you paid 300 for a key that came in and did not work with your Comfort Access and you had to spend an additional 150 to make it work, it would leave a sore spot I think.

Thank you for the encouragement.