Quote:
Originally Posted by RichardM98
There were 3 generations of Smart Keys during the W210 model. First was the biggest (about 78mm long), second smaller (about 68mm long) and third (about 72mm) with chrome sides. Neither the circuit boards or the metal (cut) keys are interchangeable.
If you get a genuine MB smart key of the RIGHT generation, that is, looks exactly* the same as yours, then you can take out the circuit board and put it in the new (used) key. Many inexpensive Chinese knockouts don't start the car reliably even though it's just a plastic case. Also, don't buy a used key thinking that the dealer will program it to your car -- they won't. 
Or you could treat your wife to a new Smart Key. About $200-$250 at the dealer and it will be a chrome one. 
* Pay attention to the shape and location of the red emergency button as well. |
The key has three functions on one side a chrome MB Star on the other side. The top has a panic button next to the thin key release.
I look at several SmartKey housing on the web. There were several on E-bay and there was one from China. I could not tell if they would be compatible with my present key. Most of the keys were under $30.00 and there were some over $50.00 on one site.
I called a few dealer around the country. The cost ranged from $225.00 to $275.00. I found a local dealer with AAA discount under $200.00. The dealers require proof of ownership. I think I will go with a new key from the dealer. It takes about one day.