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2 Cars set to same key??

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Old Aug 3, 2003 | 01:01 PM
  #1  
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2 Cars set to same key??

We're about to receive our 2nd MB. First is a 2001 E320 Wagon, and incoming is a 2004 CLK Cab.

I asked our dealer if both cars could be set to use the same key thing (the light-emitting type) since my wife and I both drive both cars and would rather not bulk up our keychains with two keys and not have to keep track of which is which!

Seems pretty straightforward, and we can't be the only 2-MB family that have this request...

yet the dealer svc. manager says no way, can't be done. Then again, they also say you can't add Nav after the fact and we all know that's doable (thanks Steve!!)...

Anyone know if this is doable? Should be something many buyers would like...

Thanks in advance for any help,

--Josh
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Old Aug 3, 2003 | 01:38 PM
  #2  
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GL320CDI / C63 Edition 507 Coupe (EDP) / E63 S (on order) / G500 / Smart Brabus
Re: 2 Cars set to same key??

Originally posted by joshg


Anyone know if this is doable? Should be something many buyers would like...
Trust me, I would be way happy if this could be done. I investigated it through every avenue available to me to try and get three of my cars onto one key... without going through it all, it appears it cannot be done. The car is not programmed to accept keys, as in most other manufacturers' systems (there's a slight security risk there that I guess DCAG doesn't want to allow). The keys are programmed to the car's allowed codes, and each key can naturally only carry one code, plus a unique identifier for the key.

This is what I've learned from training materials and technical WIS info... could be wrong, though.

-s-
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Old Aug 3, 2003 | 01:46 PM
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Wow... that's a HUGE bummer if that's right. So it's the key that decides if it's in the right car, not the car that decides if the right key is in. dumb.

I'm surprised no one at MB has thought of this... it should be an option from any service center. Maybe someone there will read this and work on it for the future... they should do something like this for multi-MB owners.

Maybe our moderator can comment if he knows or has a contact at MBUSA with whom to check or to suggest this...

thanks,
--josh
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Old Aug 3, 2003 | 02:39 PM
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Originally posted by joshg
...So it's the key that decides if it's in the right car, not the car that decides if the right key is in...
No, it is not that simple!
Keys are made for a specific car, the EZS (electronic ignition switch) too.
Before being mounted, an EZS gets programmed for a car (with a special workshop key, programmed with a key programming computer) and so are the keys (with the same key programming computer).
When you put a key in the EZS electronic codes are exchanged and various calculations are made. It is not one of both that decides if it belongs to a car but both.

For additional info, check this:
https://mbworld.org/forums/showthrea...ight=smart+key
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Old Aug 3, 2003 | 02:45 PM
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02 W163, 84 W123, 03 E39, 98 E39
MBs keyed alike

As good as the thought of carrying one key is now, think of the potential problems if you sell or if one of you cars is "salvaged" by an insurance company after an accident. Do you want somone else running arround with a key that will work in your second car?

You especcially wouldn't be able to sell one of the cars to any one you know, as most likely they would know that the keys work both cars. Too many potential problems for my taste.
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Old Aug 3, 2003 | 03:41 PM
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That's only if they knew that key is workable with your other car which isn't real yet.
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Old Aug 3, 2003 | 07:19 PM
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02 W163, 84 W123, 03 E39, 98 E39
One Key, Two MB's

Originally posted by dtkw
That's only if they knew that key is workable with your other car which isn't real yet.
It is a moot point as scorchie pointed out since it can't be done. I was just pointing out why it might not be a good idea if it was possible. Sorry I didn't make my self clear.
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Old Aug 3, 2003 | 09:18 PM
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Thanks all for the education... I now understand the issues much better. That said, it's still dumb that it just can't be done.

I have rolling-code garage door openers, but it's a cinch to teach it that I now have another valid opener, or to make one opener operate two doors, whatever i like. if i "sold" an opener, I can remove that opener from being listed as a valid one. no problem.

I know the cars are necessarily designed to be far more secure and it's a more complicated problem... but from a user's perspective it'd be great if it worked that simply.

Not a huge problem... just a little detail that I'd sure love to see from MB at some point.

Thanks again, this forum, as always, is incredibly helpful and I feel lucky to be part of a community with so many knowledgable people who are willing to educate, advise and share their wisdom!

--joshg
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Old Aug 3, 2003 | 10:50 PM
  #9  
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Your SmartKey system is light years beyond your rolling code garage door operator.

You also need to understand MB engineering. Often, they don't care what you want. Years back I went to the roll out of the W210 chassis E-Class. I asked an engineer from Sindelfingen about the lack of variable intermittent settings for the wiper. He simply stated that "Five seconds is the correct interval." His expression was "I am an engineer, and you are not...stupid."

Of course, they were working on the rain sensor system to be introduced shortly after, but again, the interval setting is not user determined, but done by the car.

The fact that Mercedes doesn't care is one thing that has made it a great marque in the past. They just made the cars they way they thought was best, and if you didn't like it, you bought something else.
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