My mercedes s 430 2001wont let the remote key turned everything was fine the everything went dead

Make sure the car battery is fully charged. Make sure your remote key has a good battery, too.
Place the remote in the ignition and watch if the red light inside the remote will blink when communicating with the car. The ignition key should be able to turn and the steering wheel should unlock. Then you can crank and start the car.

Tried moving the steering wheel firmly in one direction or the other while (gently!) attempting to turn the key? Or look for a little lever that your knuckle sometimes hits when you do turn the key.

MANY are connected to the drivers door lock, using the key , turn it to the left pause turn it to the right pause... do this twice...

recheck the newly installed equipment new doesnt meant free from defects need to test and check ignition switch and wiring

dead battery in fob or need to reprogram fob or system failure

Many People don't know exactly how to use the manual key attached to your remote to open the doors and trunk in case the battery is dead. All you have to do is slide the locking button in the back of your remote and pull the metal pre-cut key, then insert it in the trunk lock, turn key to the left and then push in. kawaboongha!!!

I had a merc 190e mine did this it was the starting motor it just went no warning at all will it bump start if its an automatic you can still bump it but you have to get a tow

This happen to me app. 6 mo. ago. I tried everything, Best bet is to go to Mercedes dealer and order new key. Mine is fine now with no problems. I found it was the only way and i haven't had any problems.

I hope you will be able to see that print

If your wife's key works fine and your key doesn't then there is a good possibility that your remote key is faulty. The alarm and locks may still work but those signals go to a different control module the when you try to start the car. If the ignition switch does not read the key then it will not allow you to start the car and sometimes not even turn the key in the ignition. Especially if there is any damage to the front part of the key where the red lens is at. Check and see if the infared signal is working on the remote key. To do this use a camera phone and go like your going to take a picture and point the key right at the lens of the camera phone. If it works you will see it on the screen. If it doesn't then you won't see anything when you push the button and hold it on the remote key. At the dealer they will probably ask for both keys and start by selling you a remote key.