Anyone in this august assemblage experienced problems w/ their Smart Keys not consistantly activating the ignition? My scenarios, with increasing frequency, are 1. Inserting key in slot provided and nothing happens ..... zero sound, zero action. Or, 2. Insert key, hear solenoid activate (unlocking steering wheel), but key won't turn. So far, eventual success is achieved by removing & reinserting key and/or turning the key 180 deg. This started several months ago in a car which is always garaged. Just completed an "A" service w/ specific request for a battery check ...... and "check" the battery's there. Subject key did not act up for dealer. Starter, lights, all things elecrtical are strong. Wondering if I'm experiencing a Smart Key battery failure?
Suggestions/ideas?

 

Opposite problem..... My key won't come out of ignition. Starts, runs, drives, but will not come out

 

WHich key do you have? If it is the newer chrome key, they are known to have problems with W210.... particularly because the infrared window in front of the key is 1/2 smaller in size than it is for the older black keys.

 

1. The batteries in the key have NOTHING to do with starting the car. The Emergency Key which comes with the car as new has no batteries and starts the car fine.

2. On the other hand, a weak car battery (<12v) will prevent the car from starting but lights and accessories will seem just fine.

3. Also, in order for the key to turn and start the car the ECU needs to confirm that the car is in Park. If that sensor is faulty it will prevent the car from starting.

To properly test the car's battery it must be removed from the circuit and have a load test performed. Any battery 4 yrs or older should be suspect. Less if you have a cheap battery.

I assume you were being facetious but an A Schedule service would include checking for battery water level and voltage with engine off and on if performed by a qualified tech.

 

I recently bought a 2001 E430 which has a chrome key. Since only one key came with the car, I need to buy a second key to have around "just in case." Can I buy a new "older-style black key" that will work in my car's ignition, or am I stuck with another chrome key? Thanks.
James

 

AFAIK MB only has chrome smart keys now. Not sure why you want an older style but I suppose you could try to 'reverse-engineer' by getting an older key on eBay and the switching the CB.

Either way, smart keys fail and it'll probably happen at the worst possible time.

 

I thought perhaps the older black keys were more reliable, but apparently not. So, I guess the "solution" is to have two keys available all the time. So it shall be. Thanks.
James

 

Actually there is one other option. When new, W210's came with two smart keys and an emergency key. The emergency key is much flatter because it can't open the doors, etc. It was designed to keep in your wallet. In the event of an emergency you could open the door with the blade key and start the car with the emergency key. If available the emergency key might be a little cheaper but less convenient. Also, be sure to shop around if possible since dealer prices vary on keys.

 

Thanks, Richard. I will investigate whether I can get an emergency key from the dealership, depending on the cost vs. another chrome key.

Also, I'm interested to find out what one could do if the "regular" key won't come out of the ignition; that seems like a pretty bad situation should it happen. Anyone know what the solution to that problem could be (other than restarting and driving to the nearest dealership)?
Beverly

 

See post #4, item #3 above. The transmission needs to be in park to remove the key. It's possible that the shift lever is in the correct position but the ECU does not think it's in park. Check the stickies on Benzworld for more info.

 

let us know if you succeed. i've not read of anyone successfully getting a hold
of these in recent years. word was this is no longer available.

 

Hi there, I know this is an old post but I am finding myself in this dilemma right now with an older Smart key.

I'm very familiar with how to change the battery, but changing the circuit board is where I'm having trouble with. I know you have had success in changing it, but I cannot seem to find the "white retainer clip" that is mentioned. I am a bit stuck as to how to remove the circuit board. What tool can I use that will unlock the retaining clip, and what exactly am I looking for?

Any help is greatly appreciated, as I am very stumped right now.