Can one key operate two cars?
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From: Central California Coast
2004 SL55, 2005 E500 Wagon
Can one key operate two cars?
The keys to my two Mercedes are identical to me, but not to the cars. I've got them on different places on the key ring, but I sometimes try to use the wrong one.
Can the dealer make adjustments to allow me to use one of the keys to operate both vehicles? You'd think they'd want to encourage you to have as many MBs as possible, and a pocketfull of identical keys wouldn't be much fun.
Jim
Can the dealer make adjustments to allow me to use one of the keys to operate both vehicles? You'd think they'd want to encourage you to have as many MBs as possible, and a pocketfull of identical keys wouldn't be much fun.
Jim
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From: Pasadena
2004 E55
The little grooved tab on the smart key can be changed to a few different colors. It's the tab that you push on in order to pop out the mechanical key. Some colors that I know of are red, green, blue, black, and grey. There may be more but I'm not sure.
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From: Valley of the Sun, Arizona
2011 E550, 2013 GLK
Originally Posted by t-bone
The little grooved tab on the smart key can be changed to a few different colors. It's the tab that you push on in order to pop out the mechanical key. Some colors that I know of are red, green, blue, black, and grey. There may be more but I'm not sure.
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From: Sacramento
'08 AM Vantage V8 - '03 E500
Originally Posted by BudC
Thanks for the tip. I just checked and we've got grey and black. I guess I would have noticed if the colors were brighter.
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It can't and shouldn't be done. Basically, if you get that "2-keys-in-one" stolen, you're in for some deep trouble and off without a spare key for either one of your cars. 
I'm sure none of us want that. 
I'm sure none of us want that.
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From: Central California Coast
2004 SL55, 2005 E500 Wagon
Originally Posted by MBE55AMG
It can't and shouldn't be done.
As to whether it should be done or not, I still think it would be a great convenience. There's nothing to say that MB couldn't give you several keys that each operate two cars, so having a key stolen wouldn't be any more inconvienent than if the key operated only one car.
Now that we're on the subject, does anyone know how the MB keys work? I assume they're communicating electronically with the car, but is it conductive? Or optical? Or radio? What's the protocol like? Does the car interrogate the key, or does the key just blast out a code?
Jim
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From: Melbourne - Australia
2004 E55 AMG
Originally Posted by MBE55AMG
It can't and shouldn't be done. Basically, if you get that "2-keys-in-one" stolen, you're in for some deep trouble and off without a spare key for either one of your cars. I'm sure none of us want that.
I'm sure none of us want that. 
c'mon! SL55 and wagon!!
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From: Australia
Originally Posted by CASL55
The keys to my two Mercedes are identical to me, but not to the cars. I've got them on different places on the key ring, but I sometimes try to use the wrong one.
Can the dealer make adjustments to allow me to use one of the keys to operate both vehicles? You'd think they'd want to encourage you to have as many MBs as possible, and a pocketfull of identical keys wouldn't be much fun.
Jim
Can the dealer make adjustments to allow me to use one of the keys to operate both vehicles? You'd think they'd want to encourage you to have as many MBs as possible, and a pocketfull of identical keys wouldn't be much fun.
Jim
Marking the keys with coloured tabs makes it simple.
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2011 E550, 2013 GLK
OK, here's my understanding of how it works. As each car is manufactured it is set up to use one of seven different key codes. Those seven codes go into a computer at the factory. Keys that work with the original code are provided with the car when you purchase it. No other car shares those seven codes....NONE!
Now if you lose a key, the factory will supply a key for the next code in sequence and the dealer will change the code in the car to the new code.
All the dealer can do is select one of the seven predetermined codes and cancel a code that had been used (to prevent a stolen key from being used).
If all of the seven codes get used then there apparently has to be a major change to the car to accept seven new codes. The sequence will start over in this situation.
Apparently Mercedes got some bad publicity in the past about vehicle theft (even though Mercedes were and are the toughest to steal). This is their reaction. As usual, Mercedes came up with something pretty far out.
Now if you lose a key, the factory will supply a key for the next code in sequence and the dealer will change the code in the car to the new code.
All the dealer can do is select one of the seven predetermined codes and cancel a code that had been used (to prevent a stolen key from being used).
If all of the seven codes get used then there apparently has to be a major change to the car to accept seven new codes. The sequence will start over in this situation.
Apparently Mercedes got some bad publicity in the past about vehicle theft (even though Mercedes were and are the toughest to steal). This is their reaction. As usual, Mercedes came up with something pretty far out.
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That's weird that it can't be done. Because on my 300E (W124), it uses two keys to operate it (one for the ignition and one for the door... they are different). I would think that if that's the case, then on other cars you could use one key for two cars.
-s-
-s-
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Originally Posted by scorchie
That's weird that it can't be done. Because on my 300E (W124), it uses two keys to operate it (one for the ignition and one for the door... they are different). I would think that if that's the case, then on other cars you could use one key for two cars.
-s-
-s-
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From: Torquay, England
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Originally Posted by BudC
BMW provide colored stickers for their keys so you can tell them apart. There should be some way to do that with Mercedes smart keys.
Mercedes usually have 'Smart' drivers. After all they have built the Smart car:http://www.thesmart.co.uk/
Regards,
John
Last edited by glojo; Feb 6, 2005 at 02:06 PM.
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From: Valley of the Sun, Arizona
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Originally Posted by glojo
Mercedes usually have 'Smart' drivers. After all the have built the Smart car:http://www.thesmart.co.uk/
Regards,
John
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From: Australia
Originally Posted by BudC
OK, here's my understanding of how it works. As each car is manufactured it is set up to use one of seven different key codes. Those seven codes go into a computer at the factory. Keys that work with the original code are provided with the car when you purchase it. No other car shares those seven codes....NONE!
Now if you lose a key, the factory will supply a key for the next code in sequence and the dealer will change the code in the car to the new code.
All the dealer can do is select one of the seven predetermined codes and cancel a code that had been used (to prevent a stolen key from being used).
If all of the seven codes get used then there apparently has to be a major change to the car to accept seven new codes. The sequence will start over in this situation.
Apparently Mercedes got some bad publicity in the past about vehicle theft (even though Mercedes were and are the toughest to steal). This is their reaction. As usual, Mercedes came up with something pretty far out.
Now if you lose a key, the factory will supply a key for the next code in sequence and the dealer will change the code in the car to the new code.
All the dealer can do is select one of the seven predetermined codes and cancel a code that had been used (to prevent a stolen key from being used).
If all of the seven codes get used then there apparently has to be a major change to the car to accept seven new codes. The sequence will start over in this situation.
Apparently Mercedes got some bad publicity in the past about vehicle theft (even though Mercedes were and are the toughest to steal). This is their reaction. As usual, Mercedes came up with something pretty far out.
Did you ever tinker with PGP as an email protector ? A bit like that !
You can attach as many as 7 keys to a car but each key is limited to the code it can associate with. Therefore if you would be silly enough to modify your car then it is possible.
Fundamentally it is easiest with two identical cars ...... from there on it may want to be the same engine ..... and from then on any differences ar4e just annoying.
Personally I would call the dealer and order the next two cars thus.
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I seriously doubt you can order two cars that will share the same key code. I thought I'd explained this pretty well but I guess I haven't.
If anyone has ordered a key for an older car recently you'll know that Mercedes have really become paranoid about this business. My wife lost her key to our 300E. I had to drive all the way over to the other side of the Valley to present myself to the dealer and provide both my driver's license and proof of ownership.
These were Zerox'ed and sent along to MBUSA with the order for a new key.
When the key came in, I had to drive over there again and go through the same process.
They aren't fooling around.
At one time all I had to do was call the dealer and give him my Vin number. When the key came in, I just went and picked it up.
If anyone has ordered a key for an older car recently you'll know that Mercedes have really become paranoid about this business. My wife lost her key to our 300E. I had to drive all the way over to the other side of the Valley to present myself to the dealer and provide both my driver's license and proof of ownership.
These were Zerox'ed and sent along to MBUSA with the order for a new key.
When the key came in, I had to drive over there again and go through the same process.
They aren't fooling around.
At one time all I had to do was call the dealer and give him my Vin number. When the key came in, I just went and picked it up.
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From: Australia
Originally Posted by BudC
I seriously doubt you can order two cars that will share the same key code. I thought I'd explained this pretty well but I guess I haven't.
If anyone has ordered a key for an older car recently you'll know that Mercedes have really become paranoid about this business. My wife lost her key to our 300E. I had to drive all the way over to the other side of the Valley to present myself to the dealer and provide both my driver's license and proof of ownership.
These were Zerox'ed and sent along to MBUSA with the order for a new key.
When the key came in, I had to drive over there again and go through the same process.
They aren't fooling around.
At one time all I had to do was call the dealer and give him my Vin number. When the key came in, I just went and picked it up.
If anyone has ordered a key for an older car recently you'll know that Mercedes have really become paranoid about this business. My wife lost her key to our 300E. I had to drive all the way over to the other side of the Valley to present myself to the dealer and provide both my driver's license and proof of ownership.
These were Zerox'ed and sent along to MBUSA with the order for a new key.
When the key came in, I had to drive over there again and go through the same process.
They aren't fooling around.
At one time all I had to do was call the dealer and give him my Vin number. When the key came in, I just went and picked it up.
Probably has more to do with that movie with the laser cut keys from Hamburg.
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From: Valley of the Sun, Arizona
2011 E550, 2013 GLK
Originally Posted by miroj
I don't think you realize how easy it is to steal a Mercedes ..... going all huff-puff over the keys is trivial. Im not interested in helping anyone find out how but I realize this is not "secret" since there are several gangs operating in Sydney who boost AMG cars without breaking anything.
Probably has more to do with that movie with the laser cut keys from Hamburg.
Probably has more to do with that movie with the laser cut keys from Hamburg.
In fact, all you need is the Vin number and a dealer will cut you a new key.
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There are multiple issues here. The key usually opens the door with a radio pulse that a reciever in the car reads. The key is programmed to "talk" to this reciever. I suppose the car reciever could be reprogrammed to "listen" for a different key. The ignition recepticle uses infrared to read a bar code inside the key. Remember the old 202 and 210 models that came with an emergency key that didn't have the transmitter but had the valet key and would start the car? That key had the bar code inside so the car could read it and start. Again, the car computer would have to be reprogrammed. Now, the door and other physical locks would have to be changed to match the different valet key. This would be a lot of change to the car, not the key, to make one key work for multiple cars.
Jim
Jim
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From: Australia
Originally Posted by JimPurdy
There are multiple issues here. The key usually opens the door with a radio pulse that a reciever in the car reads. The key is programmed to "talk" to this reciever. I suppose the car reciever could be reprogrammed to "listen" for a different key. The ignition recepticle uses infrared to read a bar code inside the key. Remember the old 202 and 210 models that came with an emergency key that didn't have the transmitter but had the valet key and would start the car? That key had the bar code inside so the car could read it and start. Again, the car computer would have to be reprogrammed. Now, the door and other physical locks would have to be changed to match the different valet key. This would be a lot of change to the car, not the key, to make one key work for multiple cars.
Jim
Jim
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From: Central California Coast
2004 SL55, 2005 E500 Wagon
Originally Posted by JimPurdy
The ignition recepticle uses infrared to read a bar code inside the key. Jim
Sure sounds it like can't be done. Thanks for the insight into the design of the system.
Jimm
