For the life of me I cannot understand how you went from two keys starting the car to now only one.

The RFID chips are identical between the two keys.

Maybe the chip came unglued from near the "front" of the FOB?

 

Maybe this one is like the thread on FB where the guy found the connector at the locking module fully corroded.

 

KDW4Him...I don't understand either. I had two working keys and now have a half working key.
"Maybe the chip came unglued from near the "front" of the FOB?"
should I take the FOB apart?
Tomorrow going to disconnect the battery and try and see if that works (as earlier suggested by Mr Miata)
I appreciate everyone's help.
Thank you,
Sandy

 

My experience - I've had to bust up the OEM casing to put electronics in a new case. If it hasn't been dropped on pavement from 5 foot or more I would have doubts about the chip shifting (not saying it couldn't happen).. if you shake it do you hear anything rattling around inside?

Note: my doubts of chip shifting - have you seen the glue job on those? And on my 04 it had a plastic "cage" to hold it in place.

 

Ummm - Wrong! Dealer can "delete" a key from working through DRBIII..

 

I asked that exact question and was told no...
ALso, when you order a new key from NeedsWings, they program the rfid to your vin, so that would have to be the same as your existing.
But, that doesn't mean the car can't be told to accept more than one RFID. IF I was the o.p., I would order a brand new key from NeedsWings for 150, and if that works, great, if not, then go from there. I think there is at minimum 2 different issues with the car, 1 the locking mechanism which is independent of the rfid, and the car recognizing the rfid on the 2nd key. Since the 2nd key's rfid will not be recognized to start the car, they cannot program the keyless entry to work either.
Also, has the O.P. tried pressing the unlock button multiple times on the working key? I only saw the it would only unlock the drivers door.
And while thinking of it, with the key in the car that works, when driving, do both doors lock automatically, or via the dash switch?

 

I agree, if the car will only accept the signals from six (?) keys then it must be able to recognize a code from each of the keys or it would not be able to tell one key from another and a million or more keys would be able to work.

As MrM says disconnect the battery and wait, then try again.
A new key from NeedsWings might prove that one or both the keys you have are no good. This might be a cheap option to learn something or a waste of $150, your choice.

The OP had his SKREEM module and the transponder around the ignition switch replaced, or so they say. The SKREEM would have to be programmed to his VIN or it would not work. Was this done or done correctly.
The shop was supposedly knowledgeable in Mercedes cars, was it capable of correctly doing any program changes to the Crossfire, I doubt it.
The VIN programming supposedly can only be done by certain vendors for security reasons.
The mechanic who did the original job should be back from his two week vacation now, go see him and get some explanations See if the SKREEM was programmed by a third party.
Do you have the original keys,was one swapped in error somewhere?
Is it possible that a used and damaged SKREEM with one key was used instead of a new SKREEM matched to your VIN? But they only had one key right?

 

Like mr miata says the FOB take apart is ugly. You might want to consider buying a new key from Needswings for diagnostic purposes. This new key would have the RFID pre-programmed to your car, the key cut for your car and you can do the simple procedure to make the buttons unlock/lock doors remotely.

 

[QUOTE=Red Paul;845654]
My car would not start, it was towed to an independent shop. The shop ordered 5099541-AA Module DO 08035031 from Chrysler. They also ordered 168-464-02-53 Transponder from Mercedes-Benz./QUOTE]

A SKREM, Power window module and the third? Transponder meaning the remote rx for the keys to lock/unlock?

If the SKREM is replaced it should have been able to "read" the existing keys or programmed to read the key RFID to start the car.

Not sure about a power window module on our cars because if I recall correctly the body control module does the windows so I am not sure how that relates to no start or no unlock/lock.

I am trying to get a complete picture of what the shops did.

 

[QUOTE=KDW4Him;845714]I think you are confusing the issue, they replaced the SKREEM module (5099541-AA) and the coil transponder (168-464-02-53) around the ignition key hole.
No window module was mentioned that I saw, the SKREEM is often called the Door Lock module.

 

MrMiata...no rattle in key fob. I've never dropped my key. Battery was disconnected for 15 mins. Nothing changed.
Pioneer4x4...I tried pressing lock/unlock many many times. Car locks automatically (both doors) when driving.
I ordered a key from Needswings. Thank you!
KDW4him..thank you for your input.
onehundred80....a million thank you's for not giving up on me and taking the time to try and figure out my crazy problem. A new SKREEM was ordered. I have the old parts. I only gave the auto place one key...my key that is no longer working at all. BUT...I ordered a new key from Needswings today.
I will start there and hopefully that will do the trick. If it works then I will order a second key.
I APPRECIATE everyone's help!
Sandy

 

[QUOTE=onehundred80;845717]
Google found several power window modules with that number. The OP had 3 part numbers in it.

So the SKREM and antenna were replaced and only one key works. Too strange. Did the dealer give the owner back the correct keys?

 

[QUOTE=KDW4Him;845768]His non working key does turn the ignition over.. so I'm going with a yes.. Wish we had the down and dirty dictionary on these damn things instead of bits and pieces we've managed to assemble.

 

Wild guess.. secret key code data corrupted during transfer???

The SKREEM retains in memory the ID numbers of any ignition key transponder that is programmed into it. For
added system security each SKREEM is programmed with a unique secret key code. This code is stored in memory,
sent over the CAN data bus to the PCM, and is encoded to the transponder of every ignition key that is programmed
into the SKREEM.
In the event that a SKREEM replacement is required, the secret key code can be transferred to the new SKREEM
from the PCM using the DRB IIIT scan tool and the ignition key system replacement programming procedure.
Proper completion of the ignition key system initialization will allow the existing ignition keys to be programmed into
the new SKREEM so that new keys will not be required. In the event that the original secret key code cannot be
recovered, SKREEM replacement will also require new ignition keys. The DRB IIIT scan tool will alert the technician
during the key reprogramming procedure if new ignition keys are required.

 

Parts replaced (I have the old parts)
5099541-AA Module DO 08035031
And
168-462-02-53 Transponder
Yes I was given the right keys back....I have red nail polish (unlock) on MY (non) working key. The non working key turns the ignition for two seconds then turns off.
Sandy

 

I don't think each key has it's own code for the RFID chip. I think both keys have the same code in the RFID chip otherwise we would have to specify which key when ordering a new one. That is why I cannot DX one key good and one key bad to start the car.

 

We will know for sure when you get the new key.

 

Well feel free to explain how the dealer can temporarily or permanently disable a key (per my DRBIII research) .. if that is the case.

And I think this might be a subtle hint to that statement also.. "and is encoded to the transponder of every ignition key that is programmed
into the SKREEM."

"every Key" not "the code" for Keys..

 

So how does the Needswings guy send you a working key IF "every key" has it's own RFID? He would have to know WHICH FOB you want replaced.

Logically looking at this would say both keys for my VIN have the same RFID so whenever a new key is needed my RFID is put into a FOB and sent to me per my VIN.

 

There is a limited number of keys you can obtain and work with the skreem.. 180 said he thought 10 .. and I don't recall exactly myself.. but that number sounds right. Chrysler keeps a database with the vins on the keys (we know this since it does take the vin for a replacement) .. so when you order a new one.. they just go to the next one on the list I'm sure..