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I am not doubting your word, this just runs counter to everything I thought about how this system works.

I thought the system used RFID chips that are pre programmed with a read only serial number and the DAS had to be taught this number to recognize the key.

I had read stories before about the DAS only being able to accept 8 keys over its lifetime. So I wonder if there is a pre programmed list in the DAS, and maybe they are able to look up a vehicle's history, and burn a new key to the next free number on the list.

I also read that if the DAS approves the key then inserting the key in the EIS synchronizes the convenience functions.

Very interesting...

Some info on keys.

I'm basing this on 97 DAS X single button IR remote with a metal flip key and would expect others to be similar enough.

The RFID chip is read / write. A single use code is sent from the key to the DAS box, verified that it is valid, then the DAS box writes a new code to the key for the next cycle.

The chip can brick if the writing process is interrupted by low vehicle battery voltage. And of course, jump starting is blamed for "frying" the computer but the damage had already occurred.

The 8 key limit refers to 8 active keys. There are 3 sub keys allowing 24 keys unless the DAS box is reprogrammed by non MB tools. The car would be issued with keys 1A and 2A. If you lose 1A, it can temporarily or permanently locked out and a 1B key issued.

The remote unlock needs to be programmed on the 97 and likely others. This consists of pressing the remote button 2X while it is pointed at the IR receiver then inserting the key in ignition and turning on.

The most direct route to setting keys down and not finding them:

Keep keys in pocket.

When they come out of pocket at end of day they always go in the exact same spot.

When was this?

This is not a new policy. It is being enforced in all of CA, not sure about anywhere else. Any MB with electronic key requires it to be physically present in the dealership or the mechanic shop with a locksmith credential before the dealership will order a new key.

Maybe that was true for the old key not needing to be programmed, but nowadays the new keys come with an orange workshop key that you MUST insert into the EIS to activate a key track to program the new key into the EIS. No orange key, no programming. Orange key job is to activate the key track -- nothing more. After use, the orange key goes straight back to HQ, or the HQ in texas to be reprogrammed for another car and reused.

ML was in July 2014
E320 was in Dec 2015

No one from the dealership ever touched my vehicles.

I ordered the keys via a phone call and an e-mail with a photo of the title and my DL. When the keys arrived, I drove the 200 miles to the dealer with my vehicle, title and DL to pick them up. I cannot remember if they even looked at my title and/or DL when I picked up the keys.

I am a known customer to the parts manager. The few parts I have to get from the dealer, he mails to me. Usually $2 o-rings or bolts or washers. He treats me like I might someday win the lottery and buy people Mercedes Benz's the way Elvis bought people Cadillacs.

OK, here's how the key ordering system really works.....The OWNER of the vehicle needs to go to the dealer with a picture ID and vehicle registration or title. Pre-pay for the new key. When the new key arrives it works right out of the box. MB key policy dictates that a dealership employee MUST verify that the new key works. If the vehicle can't be driven to the dealership, a dealer rep will go to where the vehicle is. At my dealership we use the parts delivery drivers to do this since they're on the road anyway.

There's no need to tow the car or break into it. I hope this clears things up........

jay_bob's solution was right on the money! I had to have the car towed to the dealership, present the title and driver's license and of course $352.

Thanks for all the replies and kudos to jay_bob for providing the correct answer.

Bjoern

If jay-bob's solution/position and your decree that its the "correct" answer includes the assumption that the car had to be towed to the dealership and Xentry/DAS is used to code a replacement key I can say you and he are not correct, at least for newer cars.

I've had multiple first-hand experiences ordering replacement keys that worked out of the box with no programming from Xentry/DAS required.

I believe that may not have been the case in the early 2000's timeframe but I've ordered keys from 2006 vehicle onward that didn't require dealer visits or Xentry programming involvement.

Of course maybe your dealer physically required the car to be on-site so they could verify the replacement key worked? If you had ordered it from ILUVMIL's dealership the parts driver would have dropped it off with no tow required?

On second thought the fact that your car was locked in the garage might be a complicating factor, as I recall the replacement keys have to be inserted into the lock of the car before they are activated....maybe they would not be able to unlock the car until that point but on the other hand you should have been able to use the physical key on the replacement key to gain entry into the car?

Lots of moving parts here....

I based my answers on two things:
The MB policy at this link STAR TekInfo
"Theft-relevant parts info" on the left
This clearly states that the vehicle has to be presented to a dealership representative for key replacement.

And my experience with the Immobilizer system on a Honda. These use a fixed serial number RFID chip and so if a new key is needed, the car controller needs to be programmed to the new key serial number. This also wipes out the existing programming, so it is necessary to have all the keys present at the programming session to retrain the system.

During the infamous Takata airbag recall repair on the Cr-V, they locked the keys in my car. I ended up with a free extra valet key but had to bring the other 2 original (1 operator and 1 valet) keys to the dealer so they could reprogram all the keys in.

I assumed (apparently incorrectly) that the MB system is similar to the Honda RFID system. Apparently MB has the ability to look up the VIN and program a new key to a serial number already in a table factory programmed in the EIS module. This allows a key to be brought to the vehicle in the field and it will work without Xentry.

The security implications of someone misrepresenting their need for a key dictates the MB policy. There is no electrical reason why they cannot mail you a new key to pick up, it is all about the security.

My '98 has the same fancy key as the newer cars (looks anyway). When I lost mine, all I did was take the title to the dealer, plunk down $155 (5 years ago) and then return a few days later to pick up the fully programmed key.

Not sure if this applies in the situation but seems reasonable.