Key Fob Doesn’t Work

[JNY88]

Just bought my first M3 Convertible and it came with 2 busted key fobs. I figured I’d go the OEM route and purchased 2 new keys from the local BMW dealer (crazy how expensive the keys are). The new keys are supposedly pre-programmed and I had the dealer confirm this but the fob still doesn’t work to lock/unlock the doors.

I tried all the re-program tricks I could find from other threads/posts online (turn key to position one 5 times, then hold unlock button while pressing lock button 3 times, etc) but nothing is working. Does anyone have any idea on what else could be the problem? The keys work to start the vehicle, it’s just the fob that doesn’t seem to work. Any help is greatly appreciated.

[sapote]

You didn't mention but I assume that the console lock/unlock buttons work for locking/unlocking the doors and trunk. If yes, then you might have the issue of the RF antenna to pick up the RF signal from the key fob. Check the cable harness at the upper right of the trunk near the rear windshield for broken wires inside the rubber boot.

[JNY88]

You didn't mention but I assume that the console lock/unlock buttons work for locking/unlocking the doors and trunk. If yes, then you might have the issue of the RF antenna to pick up the RF signal from the key fob. Check the cable harness at the upper right of the trunk near the rear windshield for broken wires inside the rubber boot.

yes the console button locks and unlocks the door, but the trunk button interestingly also doesn’t work. I’ll check out the cable harness as you suggest, thanks for the idea.

[Shonky]

Just to note as you've probably figured out, the keys are only "pre programmed" for the EWS ie to start the car. Basically the EWS has ten programmed slots from the factory so when you order via VIN they program the key based in one of the spare key slots.

You definitely have to program the car for the remote lock/unlock which is a completely separate function. Basically teach the car the new remote.

[Arith2]

I'm having a similar issue. Once I find the time, I'll let you know what my diagnosis is. For now, I'm just manually locking and unlocking. It's only slightly less convenient so it's low on my priority. You need to scan you car with INPA or DIS. ISTA is preferred but I don't know any reliable sources others than the real thing.

[sapote]

I'm having a similar issue. Once I find the time, I'll let you know what my diagnosis is. For now, I'm just manually locking and unlocking. .

Keep using the key manually lock/unlock can lead to broken mechanism in the door latch. It wasn't designed for activate by the key mechanically.

[Arith2]

Keep using the key manually lock/unlock can lead to broken mechanism in the door latch. It wasn't designed for activate by the key mechanically.

That's specifically what it was designed for. Whether it's remote or mechanical, those mechanisms fail regardless.

[tedbm3]

This is the method that worked for me on the first try, other methods failed

[sapote]

If the EWS has power supply issue then it could also lock out the key fob remote control (like the remove control function won't work with the key turned on the ignition sw). The EWS has 2 power sources: unswitched 12v and ignition switched 12v. If the un-switched 12v is not stable due to bad wiring or connection, then the EWS cannot tell if the key is removed or still in the ignition sw, hence the EWS disables the key to GM5 control.

[Grke46m3]

Do the m3s have the same issues as the regular e46 with the bad gm5 module relays? I’m sending mine out to Scott from bmwgm5 my 325i that is and see if it fixes my issues. Had same problem as you on my daily e46. Used the key in drivers door to unlock and then my lock broke. Had to get aaa to unlock my car and I rebuilt the lock cylinder now I’m sending my gm5 out.


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[sapote]

Do the m3s have the same issues as the regular e46 with the bad gm5 module relays? I’m sending mine out to Scott from bmwgm5 my 325i that is and see if it fixes my issues. Had same problem as you on my daily e46. Used the key in drivers door to unlock and then my lock broke. Had to get aaa to unlock my car and I rebuilt the lock cylinder now I’m sending my gm5 out.


Sent from my iPhone using Tapatalk Pro

Op GM5 relays work fine as he used the console switches.

[TropicalM3]

There is a way to check the signal from the key to the antenna, the wire that goes to the GM5 from the antenna(output side) can be checked for power when the key is pressed with a test light, I did this once with my M3 and it worked, so I know the key was sending a signal. Found out I had a blown fuse, replaced that and the central lock started to work again.