New C240 Owner.... with some questions
Thread Starter
Newbie
Joined: Nov 2001
Posts: 13
Likes: 0
From: Maryland
2002 c240
New C240 Owner.... with some questions
Hi,
I have been keeping up with this forum for the past 3 months which helped me greatly with my purchasing desision:
C240 / white / automatic / C3 [folding rear seats] / cd changer
Definitely made the right choice as far as dealer and car are concearned.
I have a few questions however:
1. I was thinking of purchasing a "club" (the locking thing on the steering wheel). However I am reminded of the movie "60 miuntes" when they were trying to steal the Mercedeces but had to have the smart keys. Is that true? Is there a way for someone to get the car started and drive it away without the smart key? If there is no way to do that then there should be no reason to get the club.
2. Brake-in period. I have read a few posts where some owners mentioned a 1000mi brake-in period of driving less than 50mph and keeping the engine under 4000rmp. My dealer or the dealer's mechanic did not mention anything about this, and I forgot to ask last night. Does this brake-in period apply for all MBs or maybe it was a c230K post I read? I will also ask the dealer today.
3. I read something on the mbusa web site or maybe somewhere else about how the smart key security mechanism works. Every time you lock the car a new encrypted shared key in between the car and smart key is created preventing someone from duplicating your key. The C240 comes with 2 keys, so my question is, how can the second key still open the doors after using the first key. I haven't tried it, and I am sure it works, but I wonder how?
Final words of advice:
"If you have been driving a '92 Ford Taurus L arond for the past 5 years, you will realy realy like a new c240 much better."
Thanks,
Dede.
I have been keeping up with this forum for the past 3 months which helped me greatly with my purchasing desision:
C240 / white / automatic / C3 [folding rear seats] / cd changer
Definitely made the right choice as far as dealer and car are concearned.
I have a few questions however:
1. I was thinking of purchasing a "club" (the locking thing on the steering wheel). However I am reminded of the movie "60 miuntes" when they were trying to steal the Mercedeces but had to have the smart keys. Is that true? Is there a way for someone to get the car started and drive it away without the smart key? If there is no way to do that then there should be no reason to get the club.
2. Brake-in period. I have read a few posts where some owners mentioned a 1000mi brake-in period of driving less than 50mph and keeping the engine under 4000rmp. My dealer or the dealer's mechanic did not mention anything about this, and I forgot to ask last night. Does this brake-in period apply for all MBs or maybe it was a c230K post I read? I will also ask the dealer today.
3. I read something on the mbusa web site or maybe somewhere else about how the smart key security mechanism works. Every time you lock the car a new encrypted shared key in between the car and smart key is created preventing someone from duplicating your key. The C240 comes with 2 keys, so my question is, how can the second key still open the doors after using the first key. I haven't tried it, and I am sure it works, but I wonder how?
Final words of advice:
"If you have been driving a '92 Ford Taurus L arond for the past 5 years, you will realy realy like a new c240 much better."
Thanks,
Dede.
Senior Member
Joined: Nov 2001
Posts: 397
Likes: 0
From: Toronto, Ontario Canada
2002 C240 Classic - Orion Blue Beast!!
Re: New C240 Owner.... with some questions
Originally posted by Dede
Hi,
I have been keeping up with this forum for the past 3 months which helped me greatly with my purchasing desision:
C240 / white / automatic / C3 [folding rear seats] / cd changer
Definitely made the right choice as far as dealer and car are concearned.
I have a few questions however:
1. I was thinking of purchasing a "club" (the locking thing on the steering wheel). However I am reminded of the movie "60 miuntes" when they were trying to steal the Mercedeces but had to have the smart keys. Is that true? Is there a way for someone to get the car started and drive it away without the smart key? If there is no way to do that then there should be no reason to get the club.
It's impossible to start an MB without the smart key. They can still steal it without the key if they want. They could tow it away.
2. Brake-in period. I have read a few posts where some owners mentioned a 1000mi brake-in period of driving less than 50mph and keeping the engine under 4000rmp. My dealer or the dealer's mechanic did not mention anything about this, and I forgot to ask last night. Does this brake-in period apply for all MBs or maybe it was a c230K post I read? I will also ask the dealer today.
For break in, follow what the owners manual says. The manual was written by the manufacturer. They know better than your dealer. I agree with not reving the engine too high during break in, but I don't think driving above 50 is a big deal. The most important thing is that you don't floor it during break in. Constantly vary your spead so that the engine get's worked in properly. Don't slam on the brakes. Just be easy on the car and you should be fine.
3. I read something on the mbusa web site or maybe somewhere else about how the smart key security mechanism works. Every time you lock the car a new encrypted shared key in between the car and smart key is created preventing someone from duplicating your key. The C240 comes with 2 keys, so my question is, how can the second key still open the doors after using the first key. I haven't tried it, and I am sure it works, but I wonder how?
Good question. I know that it does work, since I have tried it. In the end, my only concern is that the second key does in fact work if called upon.
Final words of advice:
"If you have been driving a '92 Ford Taurus L arond for the past 5 years, you will realy realy like a new c240 much better."
Thanks,
Dede.
Hi,
I have been keeping up with this forum for the past 3 months which helped me greatly with my purchasing desision:
C240 / white / automatic / C3 [folding rear seats] / cd changer
Definitely made the right choice as far as dealer and car are concearned.
I have a few questions however:
1. I was thinking of purchasing a "club" (the locking thing on the steering wheel). However I am reminded of the movie "60 miuntes" when they were trying to steal the Mercedeces but had to have the smart keys. Is that true? Is there a way for someone to get the car started and drive it away without the smart key? If there is no way to do that then there should be no reason to get the club.
It's impossible to start an MB without the smart key. They can still steal it without the key if they want. They could tow it away.
2. Brake-in period. I have read a few posts where some owners mentioned a 1000mi brake-in period of driving less than 50mph and keeping the engine under 4000rmp. My dealer or the dealer's mechanic did not mention anything about this, and I forgot to ask last night. Does this brake-in period apply for all MBs or maybe it was a c230K post I read? I will also ask the dealer today.
For break in, follow what the owners manual says. The manual was written by the manufacturer. They know better than your dealer. I agree with not reving the engine too high during break in, but I don't think driving above 50 is a big deal. The most important thing is that you don't floor it during break in. Constantly vary your spead so that the engine get's worked in properly. Don't slam on the brakes. Just be easy on the car and you should be fine.
3. I read something on the mbusa web site or maybe somewhere else about how the smart key security mechanism works. Every time you lock the car a new encrypted shared key in between the car and smart key is created preventing someone from duplicating your key. The C240 comes with 2 keys, so my question is, how can the second key still open the doors after using the first key. I haven't tried it, and I am sure it works, but I wonder how?
Good question. I know that it does work, since I have tried it. In the end, my only concern is that the second key does in fact work if called upon.
Final words of advice:
"If you have been driving a '92 Ford Taurus L arond for the past 5 years, you will realy realy like a new c240 much better."
Thanks,
Dede.
Super Member
Joined: Nov 2001
Posts: 644
Likes: 0
From: Orlando, FL
2002 Mercedes-Benz C230 Kompressor Sports Coupe
SmartKey uses private-key authentication, same thing used in PGP encryption and to protect our nuclear stockpile. I think I can explain how it works...
Each SmartKey has a unique code in it that was placed there by the car's computer. To use PGP language, this code can be called the "SmartKey's PRIVATE KEY". At the same time, the computer registers the key with the computer by giving it a unique code, which we call the "SmartKey's PUBLIC KEY". This requires that each key be pre-activated with the car's computer to work.
The computer itself has its own "Computer PUBLIC KEY" and "Computer PRIVATE KEY". It actually has one for each key that is registered with the car (hence the limit to how many keys can work at any given time).
When you insert the SmartKey into the car, it's "SmartKey PRIVATE KEY" and the "Computer's PUBLIC KEY" are used together to generate a message that basically says "TURN ON".
The computer takes this message, and authenticate's it by using the "SmartKey's PUBLIC KEY" together with its own "Computer's PRIVATE KEY" to authorize it. Once the message is authorized, the computer can activate and turn on the car.
Once this happens, the computer then generates a new "SmartKey PUBLIC KEY" and "SmartKey PRIVATE KEY", basically re-registering the key with the computer for its next use. Then the computer generates a new "Computer PUBLIC KEY" and "Computer PRIVATE KEY" for that key (stored within the computer). The net effect is that each key-code combination is only good for a single use.
One big question remains, maybe someone who has replaced their SmartKey can answer. Does the key come pre-registered to work with your car, or is there some procedure to 'register' it with the car?
How could you break past this system?
1. Replace the computer. I'm sure MB thought of this one and has some special dealer procedure, codes, etc. to initialize a new computer that is complicated enough to render this an impractical option.
2. Plug a CRAY mainframe in try millions of random combinations till you hit the right one (might take 3-6 months).
There's a third way, but I'll wait till someone answers my question. It may be moot in the end.
In short, it is pretty impossible to hotwire your car. Best they can do is tow it away on a flatbed truck. Has to be a flatbed, cause the MB locks its tires if someone tries to tow it away.
Rick
Each SmartKey has a unique code in it that was placed there by the car's computer. To use PGP language, this code can be called the "SmartKey's PRIVATE KEY". At the same time, the computer registers the key with the computer by giving it a unique code, which we call the "SmartKey's PUBLIC KEY". This requires that each key be pre-activated with the car's computer to work.
The computer itself has its own "Computer PUBLIC KEY" and "Computer PRIVATE KEY". It actually has one for each key that is registered with the car (hence the limit to how many keys can work at any given time).
When you insert the SmartKey into the car, it's "SmartKey PRIVATE KEY" and the "Computer's PUBLIC KEY" are used together to generate a message that basically says "TURN ON".
The computer takes this message, and authenticate's it by using the "SmartKey's PUBLIC KEY" together with its own "Computer's PRIVATE KEY" to authorize it. Once the message is authorized, the computer can activate and turn on the car.
Once this happens, the computer then generates a new "SmartKey PUBLIC KEY" and "SmartKey PRIVATE KEY", basically re-registering the key with the computer for its next use. Then the computer generates a new "Computer PUBLIC KEY" and "Computer PRIVATE KEY" for that key (stored within the computer). The net effect is that each key-code combination is only good for a single use.
One big question remains, maybe someone who has replaced their SmartKey can answer. Does the key come pre-registered to work with your car, or is there some procedure to 'register' it with the car?
How could you break past this system?
1. Replace the computer. I'm sure MB thought of this one and has some special dealer procedure, codes, etc. to initialize a new computer that is complicated enough to render this an impractical option.
2. Plug a CRAY mainframe in try millions of random combinations till you hit the right one (might take 3-6 months).
There's a third way, but I'll wait till someone answers my question. It may be moot in the end.
In short, it is pretty impossible to hotwire your car. Best they can do is tow it away on a flatbed truck. Has to be a flatbed, cause the MB locks its tires if someone tries to tow it away.
Rick
Thread Starter
Newbie
Joined: Nov 2001
Posts: 13
Likes: 0
From: Maryland
2002 c240
... so the cars computer has a private key for each smartkey
Flashman,
Thanks for the explanation. I figured it worked just like PGP but was puzzeled about the 2 key problem. Since you said that the car's computer has a public-private key pair for each key, then it all makes sense.
Thanks.... curious what the 3rd. option was...
Do you by any chance know what the encription key bit lenght is?(128, 64...)? I am also curious what encryption techniques they are using, whether it is similar to web browsers and digital certifictes?
Thanks for the explanation. I figured it worked just like PGP but was puzzeled about the 2 key problem. Since you said that the car's computer has a public-private key pair for each key, then it all makes sense.
Thanks.... curious what the 3rd. option was...
Do you by any chance know what the encription key bit lenght is?(128, 64...)? I am also curious what encryption techniques they are using, whether it is similar to web browsers and digital certifictes?
Super Member
Joined: Nov 2001
Posts: 644
Likes: 0
From: Orlando, FL
2002 Mercedes-Benz C230 Kompressor Sports Coupe
3rd option is based on an IF...
IF, when you order a key, it comes pre-registered from Germany. That means that there is a fourth public-private key in the computer, programmed for a "factory key". When the computer gets this key, it immediately reprograms it to occupy one of the three main key slots.
IF that is the case, then just get the VIN number, convince a dealership you own the car, and order a replacement key. Just like in the movie!
I thought of a fourth option, just steal your key from the valet, or if I want to be real high tech, build some device that lets me clone your key when you leave it on a table for a minute. Of course, the cloned key is only good for ONE use.
Rick
IF, when you order a key, it comes pre-registered from Germany. That means that there is a fourth public-private key in the computer, programmed for a "factory key". When the computer gets this key, it immediately reprograms it to occupy one of the three main key slots.
IF that is the case, then just get the VIN number, convince a dealership you own the car, and order a replacement key. Just like in the movie!
I thought of a fourth option, just steal your key from the valet, or if I want to be real high tech, build some device that lets me clone your key when you leave it on a table for a minute. Of course, the cloned key is only good for ONE use.
Rick
