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Key Fob probelm

78K views 45 replies 14 participants last post by  resunoiz 
#1 ·
I just picked up my 01 750il from a auction and I have some work ahead of me.

I have 2 key fobs.

Key Fob 1 - The battery works and it opens and locks the doors. It does NOT start the car.

Key Fob 2 - I believe the batteries are dead but it STARTS the car.


So I read about how to program the fobs and how to open and repalce the battery.
But which key would be my master to program the other? Its been a while since I owned a BMW so I am a confusded on which route to take to get them both working.

Any thoughts on how to proceed?
 
#5 · (Edited)
The remote keys have 3 totally independent features that work in conjunction with one another...many owners get confused as to which one does what etc. and often times ascribe programming features for DWA/FZV to the EWS feature of the keys...which is incorrect. EWS programming is totally different than the programming/initalizing procedure for DWA/FZV features.

The remote keys contain:
  • EWS - immobilizing feature that shuts down fuel/spark/ignition until a recognized key (which has an EEPROM chip inside with an individual serial number (ISN) that matches the other EWS components. This feature is self powering (thru induction) and DOES NOT need the battery inside the key to start the car. Neither is it "programmable" by the procedure used to program the other features...it must be synced using proprietary software/hardware to the other EWS components.
  • DWA - anti-theft alarm siren system (requires the use of the battery inside the key)...this feature can be programmed by the owner using the procedure outlined below. This feature also allows the key to be programmed to other BMWs that use the same (RF) radio frequency.
  • FZV/FBZV - central locking system/keyless entry (requires the use of the battery inside the key)...this feature can also be programmed by the owner using the procedure outlined below. This feature also allows the key to be programmed to other BMWs that use the same radio frequency.

If the battery is dead or damaged inside the key...change it (old style key or new style key)...or recharge it (new style key) by inserting it into the ignition and turning the key to at least position 1 for up to 30 hours (if completely discharged). A dead key battery will interrupt the DWA/FZV functions...but the key should still be able to start the car.

If the key won't start the car...then there's an issue with EWS. Programming the key using the DWA/FZV initialization procedure will DO NOTHING to fix this issue. Since your 01 should have the new style remote key...if it's not starting the car, but the key fits the ignition and will turn to the start position...there's probably something wrong with the EEPROM inside the key...or it's out of sync with the other EWS components. You're going to need a dealer's help or find an Indy mech or other BMW owner that has the software/hardware to access the car's communication BUS system.

Here's the instructions I've posted many times on how to reprogram the old & new style remote keys. You MUST follow every instruction to the "T"...start the 2nd & successive remote keys on STEP 3...DO NOT insert the other remotes you're programming into the ignition...if you do, you'll cancel the 1st key's programming:



(EWS EEPROM (transponder chip) location inside the new style key)



(it can take up to 30 hours to fully recharge a completely discharged new style key)
(TIP: hook up battery charger to jump start location in engine bay, insert key & turn to position 1, charge over night)


 
#6 ·
Thanks that is exactly what I was looking for.

So for my Key that starts the car but batteries appear dead - I need to charge for 30 hours. - then if they dont open the locks use the program you outlined.

The key with working battery that opens the doors currently but does not start the car - I can not program that myself.
 
#7 ·
1. So for my Key that starts the car but batteries appear dead - I need to charge for 30 hours. - then if they dont open the locks use the program you outlined.

2. The key with working battery that opens the doors currently but does not start the car - I can not program that myself.
1. Yes, try charging the key that starts the car for approx 30 hours. Once charged, try re-programming it (you'll also need to do the other key during the same session, if not...it will no longer lock/unlock & arm/disarm your car).

If it sill doesn't lock/unlock & arm/disarm your car after charging it & reprogramming it...it could be that the battery is dead or damaged (from being dropped) and a new key or "key surgery" may be required.

2. Yes, again...the key that locks/unlocks & arms/disarms your car can NOT be programmed to start your car without special software/hardware. But there are several things that could be wrong...like the key may have been lost at one point and a previous owner had it barred (see info below). Or that key may have been dropped or damaged and that's why it is not working properly...and may have a broken solder joint or other internal issue and it, too may be in need of being aligned with the other EWS components.

(key deactivation...aka...barred from the EWS system due to being lost)



 
#8 ·
Very nice explanation!:thumbup:
Since your knowledge is such vast with these modules, please explain this for me:
My friends '03 E39 has intermittent non starting situation. The key turns, but nothing happens. OEM key btw. After we did the procedure described by you in the E39 section, it start right away. The funny thing is that this happen couple times during 3 months maybe. Every time he "re-programed" the key the car start right away.
3 years ago on my E46, I had to order a key since I bought the car without ( in auction). After receiving the key from the dealership, went in "programmed" the key like described above and it start right away. For sure there was no programing done through software.
I'm curious how was that possible if the procedure described here does not comunicate with the EWS? I am convinced that the procedure communicates with the EWS module since I've done it on E38, E39 and E46, and it worked. Or maybe, I misunderstand the lines up here...
I am all ears...:rolleyes:
 
#9 · (Edited)
EWS transmits on 125 Khz AM signal - FZV/DWA transmits on 315 MHz RF signal

It's simple to understand once you know how the 3 features in the remote key (EWS/DWA/FZV) all work in conjuction in the key...but are 3 independent systems. Take note that the information below mentions DIS & MoDic in communicating with the EWS system...this is now done with BMW's GT-1 (MoDic is now outdated). That is how you communicate with EWS other than...the data between the EWS components communicate with each other over the 125 KHz AM radio frequency.

The EWS system communicates on a totally different RF (radio frequency) than the DWA & FZV features of the key. There could be multiple reasons why the car's didn't start in the scenarios you presented. It could be as simple as the key was turned too fast in the ignition not allowing the Ring Antenna to read the key's ISN code...which is required to allow the car to start.

EWS is different from FZV & DWA in one major way in that it operates using an ISN (individual serial number) that is used in all of the EWS components. The EWS chip (inside the key) is a transponder...and a transponder communicates in 2 directions...it receives as well as sends communication over a 125 Khz AM signal that is sent from the EWS control modoule to the Ring Antenna (or the transmitter/receiver if your car has EWS II). The chip inside your key comes from BMW already with the transponder coded with the ISN that is specific to your car's VIN. (btw, did you remember if you even tried to start your E46 with the new key before programing it to lock/unlock & arm/disarm the car?) There usually is no need to have to do anything when purchasing a new key for it to be able to START your car...unless the EWS components have become unsynced. But you DO need to program the FZV/DWA so that you can lock/unlock & arm/disarm the car.

And even if you do reinitialize/program a new remote key in the dealers parking lot...when you get home...your old remote key will still start the car but won't lock/unlock & arm/disarm the car because it will not have the same coding due to it being absent from the process back in the dealer's parking lot. To get both keys to perform FZV/DWA...you will have to reprogram both keys again, during the same session.

The DWA/FZV features are transmitted over a 315 MHz radio frequency (one-way communication only) to the receiver that is in the C-pillar (in North America...Europe and other markets use 433 MHz). That data is then passed on to the GM (general module) & DME.

Again, a new remote key purchased from the dealership...comes already programmed with your car's ISN which is based specifically on your car's VIN (which must be presented along with proof of ownership before the key is ordered):

(TiP: pay attention to the WORKSHOP HINTS that is in the gray boxes in the info below & in the info I previously posted)






Also, depending on your e39's build date...it could have EWS II, EWS 3.2, or EWS 3.3...obviously each iteration brought some changes (like combining the features of the transmitter/receiver into the EWS control module starting with EWS 3.2:

 
#10 ·
Thank you for the nice detailed explanation.:)
What about the E39 that gets "de-synced"? What could cause the module to "forget" the key? Is coding necessary not to have these problems in the future?
Thanks again for making light in the tunnel.
 
#11 ·
EWS components can get out of sync when something major happens...like a power surge, or if one of the components is disconnected/swapped/replaced with another component that's not coded to the car (by owners unfamiliar with the idiosyncrasies of EWS). For instance, if your car falls under EWS 3.3...it contains "rolling code technology" which changes a series of numerical tables with each use...so again, if an electrical surge interrupts a component or a foreign module is inserted into the mix and a failed attempt to start the car occurs...the components can become "unsynced". But under most situations...this is rare.

The FZV/DWA features get out of sync more often than the EWS components due to owners reinitializing a key in an attempt to restore one of the keys features...but only has one of their remotes with them during the session. Thus the other key will no longer remotely lock/unlock & arm/disarm the car. They then redo that key (and not the other)...and it becomes the "dog-chasing-his-tail" scenario. :)

Here's more EWS info about how all 10 key positions of the EWS control module are coded at the factory when the car is at the factory. Those key positions are then stored until an owner makes a request for a new key, the chip is then installed into the key of choice and sent to the owner. This is another example as to why performing the key reprogramming instructions has NO affect on EWS. EWS chips are already programmed to your car from when it was manufactured at the plant in Dingolfing Germany. :D

 

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#13 · (Edited)
Well, my Panosonic Batteries finally arived and I sliced open my keyfob to start surgery.
However I measured my existing battery and it was putting out 2.83 V. I would believe this is plenty. I did try the sync process previously and it did not work.

So what else can I test to see if it is putting out RF? all the solder joints look ok so far.
The Key starts the car so I assume the EWS / EEPROM is working fine.

I checked all the buttons using continuity and they are working.
I put a scope on what appears to be the RF antena (squiggly copper path on Circut board) I put one probe on one end and the other in close proximity. When the buttons were pressed I saw a spike on my scope.

I assume the microprocessor is working because it is reading the EEPROM otherwise the car would not start.

So I am at a loss for waht to check next.
 
#14 ·
...I assume the microprocessor is working because it is reading the EEPROM otherwise the car would not start. ...
See post #9 above. EWS does not communicate over the same RF nor transmit directly to the receiver for the FZV/DWA (central locking/anti-theft alarm siren system). Since the car is starting with no problem...remove EWS from the equation...that function of the key is working correctly.

If the key is not locking/unlocking the car and arming/disarming the car...the problem is with something between the key's transmission of the 315 MHz signal sent to the receiver in the C pillar for the central locking & anti-theft alarm siren systems...especially if one key is working fine. Then perhaps something may be wrong with the key?
 
#15 ·
Ok, since I didn't get a response to my question on the other forum, I'll try here: my two keys are able to start and manually lock/unlock the doors and trunk, also the central locking button works and fuel filler door locks normally. However, my key fob remote functions do not work. I have the older style, 3-button key with CR2016 battery. Both batteries were changed yesterday. I tried the key initialization process several times but still does not work. Any ideas?
 
#19 · (Edited)
Not sure which intializing procedure you followed...there are multiple instructions out there...some of them are incorrect. Since we are not there when your reprogramming your keys...all I can suggest is that you follow the instructions below to a "T". You can NOT fudge, combine, skip, ignore any of the steps...if not failure will occur.

Also let us know if the red LED is illuminating...if it is barely illuminating or weakly illuminating...then the new batteries may have discharged while sitting on the shelf.

Make sure that:
  • you lock/unlock the car manually from outside
  • all doors are shut
  • turn ignition to POSITION 1 (position 2 or 3 may result in failure to program)
  • only insert the FIRST key...start the 2nd key on STEP 3 (with pushing the buttons etc)


HINT: KL R = ignition position 1

 
#17 ·
Thanks but I have two keys. The second one is less than two years old bought from dealer for $135. I'm going to take it back to the dealer since its still under warranty.
 
#20 ·
Q: Yes, I have been following only your instructions to a T. Both keys are able to get to step 5 (the syncing phase) where I press button 1 three times and the LED light flashes for about ten seconds trying to sync up with the DWA but nothing happens. I haven't checked the transmitter yet in the C-pillar to see if a wire is loose or the module is dead.
 
#21 ·
If you lock the car manually with the key...take a look at the DWA red LED (on top of the dash) to see if there may be an issue with one of the DWA "monitors"...perhaps one of the not so easy to find/see monitors is staying open.

The chart below should give you an idea of what to look for (as far as the LED flashing):

 
#22 ·
Yes it is in the disarmed state. No LED. Faulty module somewhere?
 
#23 ·
Q:if one of the monitors is staying open what is the fix?
 
#24 ·
Update: My #28 fuse (remote control) under hood was missing?!! Replaced with 5 amp fuse and everything (keyless remote and DWA alarm) works again! Back to basics.
 
#25 ·
2 keys 1 ok / 2nd sorta dead

If the battery is dead or damaged inside the key...change it (old style key or new style key)...or recharge it (new style key) by inserting it into the ignition and turning the key to at least position 1 for up to 30 hours (if completely discharged). A dead key battery will interrupt the DWA/FZV functions...but the key should still be able to start the car.

Programming the key Since your 01 should have the new style remote key...if it's not starting the car, but the key fits the ignition and will turn to the start position...there's probably something wrong with the EEPROM inside the key...or it's out of sync with the other EWS components. You're going to need a dealer's help or find an Indy mech or other BMW owner that has the software/hardware to access the car's communication BUS system
.
------------------------------
have a set of 2 keys, (just got a used 2001 740iL) appears that 2nd key was never used by original owner ad I suspect the battery is dead or not initialized, will manually open doors, and start engine. First key is OK- does everything properly.

question is... If I follow the the procedure and re-program 2nd key, do I also have to do the same for the first key, which is not a problem
 
#26 · (Edited)
Any remote key not present and initialized during the same session...will no longer lock/unlock & arm/disarm the car (FZV/DWA).

After using the 2nd key for awhile to recharge its battery...when you begin to reintialize them...insert the fully working key first...then within 30 seconds start the 2nd key on STEP 3 where you start pressing/holding the buttons.
 
#28 ·
Hi QSilver7,
Thanks for that very very extensive explanation. The weird thing about my second key (I bought off Ebay) is: that I can get it to start the car, but then the master does not start the car anymore.

I did not realize at the beginning that opening the doors and starting were two different function of the key. I just assumed that if the doors open, it will start the car.

I messed around with some of the procedures floating around on the net and I finally got the second key fob I had bought of Ebay to start the car but then the master key would not work. Further more, after driving the car with the second key fob and shutting down the engine, the second key fob would not work/start the car again?? How weird is that is the EWS has to be programmed.

Maybe the second key fob worked because I had just 5 seconds before trying it started the car with the master key?
 
#29 · (Edited)
Yes...there is a 10 second period right after shutting down the engine with a working key, that EWS is temporarily disabled...this means that any key with the correct "cut" (regardless of a working EWS chip or not) can actually start the car if it is inserted into into the ignition.

You can see it mentioned in the the gray-out workshop hint in the pic below:

 
#31 ·
E38 key transmission 315mhz

I just purchased a new key from the dealer. Key starts the car. they tried to program the lock/unlock buttons but couldn't. Ive been reading the posts and learned of a transmitter in the C pillar. I looked in my C pillar and saw a bunch of wires. What does it look like? What am I looking for? I was also told by the dealer that on the 1999-2000 models, depending on when the car was manufactured and released, the key operates on either a RF signal or IR. How do I know which one it is? Is it possible that the key wont program due to transmitter/receiver module located under the dash?

Thanks!
 
#32 · (Edited)
I just purchased a new key from the dealer. Key starts the car. they tried to program the lock/unlock buttons but couldn't. Ive been reading the posts and learned of a transmitter in the C pillar. I looked in my C pillar and saw a bunch of wires. What does it look like? What am I looking for? I was also told by the dealer that on the 1999-2000 models, depending on when the car was manufactured and released, the key operates on either a RF signal or IR. How do I know which one it is? Is it possible that the key wont program due to transmitter/receiver module located under the dash?

Thanks!
The way to tell the difference between an RF & IR system...is to look at your key. If your key only has 2 buttons on it, then it is the IR key, thus you have the IR system. The RF key has 3 buttons...and also, if you look up your VIN, you will see the option "S876A FUNKFREQUENZ 315 MHZ (Radio frequency 315 MHz)". I'm not sure why your local dealer doesn't know that BMW NA didn't import any e38s to the states with the IR remote key...they were all the RF (315 MHz) keys (for both the old style & new style keys).


Before tearing into your C pillar...have you checked your fuel filler door to see if it is locking with the rest of the car? If not, lock the car with the key (manually in the driver's door lock cylinder) then walk around to the fuel filler door to see if it is locked. If it's not locked...you've come really close to finding the culprit.

The remote lock/unlock won't work if an actuator in the central locking system is not working...and the fuel filler door is part of the central locking system. Check the fuse in the trunk (it's number and position is listed on the back of the battery compartment's pull down door. Pull that fuse to see if it is blown...replace it if it is...then try to reprogram the key. If the fuse blows again, then the actuator is probably the culprit and you can either replace it, or unplug its electrical harness if it doesn't bother you if the fuel filler door never locks.
 
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