Key fob stopped working - Trunk pops but doors won't lock/unlock with remote

[FusionZ06]

I have a 2003 540i sport with the new style key.

I have two keys and both do the same thing. The unlock/lock on both keys do not work. However, the trunk open works on both remotes. I am assuming, based upon the fact that the trunk opens, that the batteries in both remotes are still good.

After manually locking the car, sticking the key in the door and turning to the right, the gas cap door does lock (I've done some searching and research).

I checked through all the fuses and none appear to be burned. I've even replaced suspect fuses.

Further, the center console lock/unlock button does not work either. The only way to lock the car is to stick the key in the door.

The alarm on the car also stopped working. The siren doesn't work anymore. The lights flash like crazy and constantly - especially when it is windy...However, that's kind of a secondary issue.

Ideas?

[thetinpusher]

I have a 2002 530I with exactly the same problem. I have replaced the battery (saw a 1 volt voltage drop on the battery under load, shorting possibly?), and checked both ground straps. Both are clean and making a good connection. I am taking mine into the dealer tomorrow to have them put it on the GT1 and see if they can track it down. It may just need to have the key re-initialized or the key could be bad. Wish I had some answers for you, so far I am still investigating myself....

Has nobody else had to deal with this?

[FusionZ06]

I have a 2002 530I with exactly the same problem. I have replaced the battery (saw a 1 volt voltage drop on the battery under load, shorting possibly?), and checked both ground straps. Both are clean and making a good connection. I am taking mine into the dealer tomorrow to have them put it on the GT1 and see if they can track it down. It may just need to have the key re-initialized or the key could be bad. Wish I had some answers for you, so far I am still investigating myself....

Has nobody else had to deal with this?

Thank you for your post! So happy to see another victim (while I'm sure you aren't).

Will you please update me as to the resolution, that is, if the dealer can find out what's going on? Thanks

[thetinpusher]

I wont get the car into the dealership until Monday. So, it will be Tuesday before I have any answers. Anybody else out there experiencing these problems?

[g2tegracer]

I had this same problem until one night I was waiting in my car for someone. While waiting I had the car off, key in ignition and messed around with various settings (I have nav). Went out for the night and when returning to my car I noticed that when I unlocked it the interior lights actually came on. So I tried using the FOB to lock/unlock it and it suddenly it worked.

I wish I knew exactly what I did to make it work again, but at least it's something?

[wileoutz]

my stopped working to i think its a gm3 error

[cdb3113]

My main FOB now unlocks the car and the trunk only. Once in a few weeks it will also lock the car. Instead, when I try to lock the car, the interior lights come on briefly. Also, my alarm kept going off yesterday when the car was parked on an incline. I haven't had it do that again yet, though.

[RandallPhoto]

I had this problem once, and it turned out to be one of the fuses in the trunk above the battery was blown..

[apache5]

i bought this car in the summer,key has never worked. opens everything manually,...inside button works,gas door locks when car is locked from the outside, no fuses blown,cant figure out the problem? even switched out the antenna receiver in the rear pillar. car is a 2003 540 m sport.

[FusionZ06]

my stopped working to i think its a gm3 error

Yeah I got an email address to a guy who supposedly fixes these GM3 issues. He said he's working on a fix for the e39...He says he is close.

Who knows...What exactly is the GM3?

My main FOB now unlocks the car and the trunk only. Once in a few weeks it will also lock the car. Instead, when I try to lock the car, the interior lights come on briefly. Also, my alarm kept going off yesterday when the car was parked on an incline. I haven't had it do that again yet, though.

Yeah - see mine keeps having the alarm go off. Well, at least the lights flash but the actual alarm itself is shot from it going off so much.

I had this problem once, and it turned out to be one of the fuses in the trunk above the battery was blown..

Checked all the fuses multiple times. Replaced them also.

[moyendevivre]

Well,

I've experienced this I will try to spare you some trouble. In my case, it was a malfunctioning key but this is the least likely culprit.

Verify you have at least one good working key. If both keys are exhibiting the same problems then we can assume that the keys are still functional.

Follow the procedure for re-initializing the key to the remote entry system. Search for the procedure, it's very easy.

Next, disconnect the fuel door locking mechanism. This can be done by opening the trunk and disconnecting the connector next to the lime green pull chord. (rear right compartment, roughly 10 inches from fuel door)

Hopefully this fixes your problem.
In my case, once the key was re-initialized I had good functionality for several cycles and then the symptoms would return. If this is the case, it is most likely a bad key.

If you still have trouble...
It sounds like a General Module III Issue. The GMIII is responsible for controlling all locking mechanisms, sunroof/windows, some alarm features, audible chimes and something else that escapes my memory.

It's really just a couple banks of relays on a printed circuit board.

It will run you between 1/2-1 hours of bench time for your local dealer to recode it to your car. Usually less than $120

The GMIII is located under the passenger glove box. It's a cryptic white box about 7-8 inches long. 1 inch tall and about 3 inches wide. It has three connectors in the back.

I have one laying around that is fully functional. I will sell it for a reasonable price. I don't really know what it's worth.

[C019740]

you guys have gas door locks? I dont and its an 03 540 I M Sport.

[wileoutz]

general module III which controls alarm central locking etc. It has relays which tend to fail over time so thats what my problem is.

[moyendevivre]

Hrmm, I think you do.
Perhaps the twistlock mounting component broke and the locking cable receded back into the body.

Open the fuel door, look on the left and see if there is a 3/16" diameter hole. Look in hole, find aforementioned cable and buy a new twist lock mount.

If you open the fuel door and lock on the inside of the actual door you'll see the corresponding housing that the cable fits in.

[C019740]

There is a hole which apears to be the lock. I dont think I care if it works or not but I dont see any release for it in the car or the key chain.

[jamesdc4]

There is a hole which apears to be the lock. I dont think I care if it works or not but I dont see any release for it in the car or the key chain.

The fuel filler door locks/unlocks with the central locking system. There isn't a sperate dedicated fuel filler door lock button.

[SecretAznSauce]

did you do a search?

http://forums.bimmerforums.com/forum....php?t=1566667

[thetinpusher]

I wanted to wait until I got the car back and checked that everything functions as it should. I took the car to a dealership and had them run a diagnostic on my electrical system. The problem was traced to a faulty GM (General Module), module replaced, everything works. I hate tracking down shorts and I didnt want to just throw parts at it. I dont have the necessary tools to do the kind of diagnostic that the dealer can. So, the GM is $400 bucks, I havent looked in my Bentleys to see how difficult it is to replace this. But all of my issues have been resolved.

[FusionZ06]

I wanted to wait until I got the car back and checked that everything functions as it should. I took the car to a dealership and had them run a diagnostic on my electrical system. The problem was traced to a faulty GM (General Module), module replaced, everything works. I hate tracking down shorts and I didnt want to just throw parts at it. I dont have the necessary tools to do the kind of diagnostic that the dealer can. So, the GM is $400 bucks, I havent looked in my Bentleys to see how difficult it is to replace this. But all of my issues have been resolved.

Sweet! Thanks!

Anyone know how hard it is to replace?

did you do a search?

http://forums.bimmerforums.com/forum....php?t=1566667

Yes - how hard was the install?

Well,

I've experienced this I will try to spare you some trouble. In my case, it was a malfunctioning key but this is the least likely culprit.

Verify you have at least one good working key. If both keys are exhibiting the same problems then we can assume that the keys are still functional.

Follow the procedure for re-initializing the key to the remote entry system. Search for the procedure, it's very easy.

Next, disconnect the fuel door locking mechanism. This can be done by opening the trunk and disconnecting the connector next to the lime green pull chord. (rear right compartment, roughly 10 inches from fuel door)

Hopefully this fixes your problem.
In my case, once the key was re-initialized I had good functionality for several cycles and then the symptoms would return. If this is the case, it is most likely a bad key.

If you still have trouble...
It sounds like a General Module III Issue. The GMIII is responsible for controlling all locking mechanisms, sunroof/windows, some alarm features, audible chimes and something else that escapes my memory.

It's really just a couple banks of relays on a printed circuit board.

It will run you between 1/2-1 hours of bench time for your local dealer to recode it to your car. Usually less than $120

The GMIII is located under the passenger glove box. It's a cryptic white box about 7-8 inches long. 1 inch tall and about 3 inches wide. It has three connectors in the back.

I have one laying around that is fully functional. I will sell it for a reasonable price. I don't really know what it's worth.

I'm interested in your used one.

How much are you thinking?

eBay they go anywhere from $80-$150.

Any idea how complicated the installation would be? Also, are they cross-compatible?

[fijimon05]

The fuel filler door locks/unlocks with the central locking system. There isn't a sperate dedicated fuel filler door lock button.

Im not sure what you meant, but there IS a sort of "emergency" gas door unlocking thingy in the trunk. It's this cord that you pull and it pops the gas door open.

[SecretAznSauce]

Sweet! Thanks!

Anyone know how hard it is to replace?



Yes - how hard was the install?



I'm interested in your used one.

How much are you thinking?

eBay they go anywhere from $80-$150.

Any idea how complicated the installation would be? Also, are they cross-compatible?

takes all but 6 minutes if you're slow. 45 seconds if you know your way around. best thing is to pull your old one out. i belive the 6 has the low and v8's have the high

[gnilson]

i bought this car in the summer,key has never worked. opens everything manually,...inside button works,gas door locks when car is locked from the outside, no fuses blown,cant figure out the problem? even switched out the antenna receiver in the rear pillar. car is a 2003 540 m sport.

Anybody try changing the battery in the key? I did and cured all ills. Its cheap and easy and took 45 secs.

Geoff

[Qsilver7]

For those with build date from 9/99-up...they aren't as lucky...their keys are the new style type (diamond shaped) and are SEALED. And if they do slice open their key, the battery is soldered to the IC board, then they will have to find an adhesive to reseal the key if they do find a replaceable battery and solder it to their key's IC board.

So yes, if you have the old style key, it's VERY easy to replace the battery...if you have the new style key...it's doable, but not so easy.

And if you're not familiar with the two types of keys, see them below...old style w/replacable battery (on left)...and new style with rechargable battery (on right):

-