2000 740il remote door unlock/lock (key)
putergeek
12-04-2003, 12:41 PM
Suddenly my key will not remotely lock and unlock my doors/trunk. I found on another forum a sequence to "re-initialize" the key - tried it and it did not work. Before I go to the dealer I wanted to see if anyone has any ideas? Could the battery in the key be bad/dead? If so can the battery be replaced or should I just not mess with this and go to the dealer?
TIA
George
<edited for spelling errors>
TIA
George
<edited for spelling errors>
jcarey
12-06-2003, 10:21 PM
If that won't do it then I'd try a dealer.
Good luck,
Good luck,
ibew595
12-07-2003, 01:21 AM
If you do not use the key for a few months then the battery will go dead. It is non replaceable but, can be charged just by using it. It is like those toothbrushes that sit in a cradle without any electrical contacts. Try finding another site with re-initilizing proceedures and see if that works, otherwise you are goobered.
libertylover
12-07-2003, 05:12 AM
1) The battery for my '93 740iL is in fact replaceable. Even from the dealer, they're not expensive. The guy at the parts counter will probably do it for you.
2) Check this: On my remote there is a small, red LED. When you press the button, the LED lights up to indicate that it is transmitting. If it doesn't light, your not transmitting, i.e., probably the battery is dead.
3) Info: For added security on my Olds van, a new code is transmitted every time you press the button. The receiver tests a received valid code against what it has stored in its memory. If it does not match, it tries the next code looking for a match, and the next, and the next... If the transmitter and receiver get out of sequence by more than 256 times, the dealer will have to reset them with special tools. BMW probably does something similar.
4) It's possible your problem is with the receiver (in the car) and not your hand-held transmitter. However, I'd bet on a dead battery in the transmitter. Try your second remote. If that unlocks the doors, the problem is in your transmitter. Good luck.
2) Check this: On my remote there is a small, red LED. When you press the button, the LED lights up to indicate that it is transmitting. If it doesn't light, your not transmitting, i.e., probably the battery is dead.
3) Info: For added security on my Olds van, a new code is transmitted every time you press the button. The receiver tests a received valid code against what it has stored in its memory. If it does not match, it tries the next code looking for a match, and the next, and the next... If the transmitter and receiver get out of sequence by more than 256 times, the dealer will have to reset them with special tools. BMW probably does something similar.
4) It's possible your problem is with the receiver (in the car) and not your hand-held transmitter. However, I'd bet on a dead battery in the transmitter. Try your second remote. If that unlocks the doors, the problem is in your transmitter. Good luck.
ibew595
12-07-2003, 12:30 PM
Liberty lover,
This does not apply to a 2000 they changed the key to one which gets charged while driving.
This does not apply to a 2000 they changed the key to one which gets charged while driving.
libertylover
12-08-2003, 04:27 AM
But if it's charged while driving that means it still has a battery of some sort.
Before your last reply, I was wondering if it might not have a battery at all. I have a Sieko watch that has no battery. It has a capacitor to hold the charge needed for the electronics and the capacitor is kept charged via the movement of your wrist. Trouble is, the original capacitor didn't last any longer than a battery.
Bottom line: mine has a battery but I don't know how the newer ones work. :-)
Before your last reply, I was wondering if it might not have a battery at all. I have a Sieko watch that has no battery. It has a capacitor to hold the charge needed for the electronics and the capacitor is kept charged via the movement of your wrist. Trouble is, the original capacitor didn't last any longer than a battery.
Bottom line: mine has a battery but I don't know how the newer ones work. :-)
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