My car is Mercedes R350 BlueTec 2011, now both smart keys are not working can somebody give me some idea?
Symptoms:
1. I can insert the smart key into the ignition, and turn it, but there is no response from the car, seems the car did not find the key. but if I keep trying many times(10 - 20 times), I probably can start the engine sometime. if I stop the engine, I will need to try another 10-20 times to start it.
2. SmartKey battery has been changed multi-times, even tried the battery which was bought from Mercedes dealer's parts department.
3. In the morning, I can use the smartkey to start my car without any problem, don’t need to try 10-20 times, just one time try, and then engine started. probably just because the car is cold. Once I drive the car for a couple of minutes, and stop the engine, I will have trouble to start my car again.
4. Smartkey has no problem on opening or locking the door at anytime. I can open or lock the door by pushing the button on the smartkey or use the door knob. Seems my car can find the smartkey at anytime, if it’s for opening or locking the door, that’s really smart.
5. Keyless Go button has no problem on starting my car at anytime, don’t need to try many times, this is the way what I am using to drive my car, leave the keyless go button in the ignition all the time. Just push the button to start the engine, and push again to stop the engine, everything goes fine. Maybe this is designed by Mercedes on Purpose, try to use one button to do everything.
6. I have two smartkeys, I have tried all scenarios, like use one smartkey for couple of days and use another one for another couple of days, replace batteries multi-times for each of them, put one key in my pocket, or both key in my pocket, even in my different pockets. Seems there is only one result: both of them have the same problem.

 

If it is a keyless go car I didn't know you could still use the standard ignition receptacle to start, I thought you always had to use the keyless go button, But if everything is working, such as the keyless entry buttons on door handles and the keyless go button for stopping and starting, it must be an issue with the ignition receptacle, that would require a visit to the dealer. I would also say if it has keyless go like you say, just leave the key in your pocket and use the button like you are supposed to. you don't have to even put the key in the receptable.

 

Finally, send the car to dealer, they replaced the whole EIS/EZS IGNITION SWITCH, it cost me about $1300.00.
Here are the details:


541011 QUICK TEST PERFORM
540650 ON-BOARD POWER SUPPLY VOLTAGE MAINTAIN
468062 IGNITION LOCK, ELECTRONIC REPLACE
468065 WORKSHOP KEY PROGRAM


1 164-905-16-99 EZS SWITCH $733.00
1 126-990-03-12 SCREW




Problem solved!