WHAT'S UP ALL???? I NEED SOME HELP PLS.. MY 2000S500 KEY WONT TURN.. I WAS TOLD THAT IT COULD BE THE BATTERIES IN THE KEY.. I CHANGED THEM AND IT STILL WONT TURN... THEN I WAS TOLD MAYBE ITS THE "TUMBLER" IN THE IGNITION.... CAN ANY ONE SHARE AN EXPIERENCE WITH ME BEFORE I GO OUT AND BUY PART AFTER PART... IM TRYING NOT TO GO GET RAPED BY THE DEALERSHIP...HELP !!!!!

 

Sounds like you only have one key avail. If you have another, try it. Does the key lock/unlock the car? When you insert the key in the ignition, you should hear a noise which is the steering lock disengaging. Put the key in ignition and open the drivers door, does it say "remove key" in the cluster? These are basic functions that must be checked first. I would likely order a key first and try that. The keys must be ordered from the dealer by vin. you will need valid registration and license to order. You will get the new style chrome key, so it must get a new blade too. Probably 150-170 bucks at a decent dealer. You cannot reprogram ebay keys!!! The key is self programming, insert it into EIS/ignition switch and the red light on the key should illuminate momentarily and will go out once programmed. See if it works then. If not, you will need an EIS and it must be replaced by the dealer and will be like 500-700 plus labor. Sucks, I know. If the old key(s) are good, they should work in the new EIS if needed.

 

The key communicates with the EIS (Electronic Ignition Switch) when it is inserted.
Failure to communicate results in the key not turning.
Power is provided for this handshake process via an inductance ring in the EIS.
The batteries in the key support remote locking.
Sounds as though its the EIS.
High mileage?
Due to the cost of the EIS I suggest you get the vehicle put on SDS Star at the dealer.
The codes will reinforce this spot diagnosis.
Agree a price for code reading up front with the dealer for this job and you will avoid any misunderstandings AND request that the results are in the form of an SDS Quick Check hard copy report

Stuart

 

I am going to argue a bit with Stuart's ideas. It is a 50/50 between key and EIS. You can hook up the sds and it will tell you what key is inserted but if the key is faulty, it will not recognize the track (could be due to failure of either component). on the other hand, if the eis is faulty, you may have CAN communication fault codes or it may work as normal and not recognize a key. On the older EIS, the failure will commonly be the microswitch which detects a key in the ignition. You should have more than one key so that would be the best to order first. Dealer meathod of diagnosis
Short test for obvious can faults in EIS, try another key (may charge 0.5hrs to program, BS), if that does not work they will likely replace EIS. So there is a high likelyhood that the dealer will require you to purchase a new key anyway to ensure proper diagnosis.

 

@ MBTechInfo.

I'm always willing to learn and there is always something new to understand with MB!

Maybe you can add a little more detail. Where specifically do you disagree with me?

Just the 50/50 chance of Key vs EIS or something else.
I accept I went a little too strong on the EIS rather than the ke. This was brought about since I did not consider the state of the key batteries to be relevant.

Which type of EIS is used on w220 @2000? In your terms old or new.

I don't understand your quote "it will not recognize the track". The w220 uses a "blunt" type plastic key to turn the ignition switch without the use of a conventional blade which is "available" but only used for emergency door access. Of course USA security is different to European which may have a bearing on the issue but I'm confused now.

Any additional information would be welcomed.

Surely EZS - Electronic Ignition Switch Quick Test has a number of codes other than CAN fault if the key and EIS fail to communicate?

Stuart.

 

It would help if you had another key, Smart-Keys do go bad, ordering a (additional)key would be a test. I dont suggest ordering a replacement because it wipes out the other forever. There have been some that have cleaned the lens and opening with a Q-tip.

 

RE: Stuart. Yeah, i'm not trying to be rude. The EIS recommendation came across a bit strong, that's all. I just wanted him to do a basic function check prior to the dealership visit, hopefully avoid it. Make sure the microswitch inside the EIS recognized that a key was inserted, and if so to try a second key. The last two I had were bad keys (still unlocked cars) but not recognized in eis. I really have had very few failures lately. You and I both realize that this is a simple diagnosis, especially with use of SDS but trying to present the case to a person who may not be as technical is difficult. sorry for coming across badly myself.

 

MB TechInfo.
Nope. I wasn't upset.
Just thought I could learn something. This remains valid.

You say "faulty" keys would still open door. Did you mean when the key inserted in the door lock barrel or using the key remote "unlock" command?

My (limited understanding of this system) is that the door "unlock" using either the door lock barrel (i.e. using the key blade = MECHANICAL) OR the remote RF transmission (requiring good batteries in the remote), is entirely different to what happens when the key (blade retracted) is entered into the EIS.

The EIS is a very complicated gateway for all the ECU modules around the vehicle but the part that allows the key to turn is part of the EIS itself.

On DAS3 (Drive Activation System) which is fitted to the w220 (2000 SClass) the following sequence occurs when the key is inserted. Firstly the key is authorised. Then the steering colum is unlocked. Then the key is unlocked (i.e. It can be turned) and finally the ME control unit for ignition etc is enabled via the CAN (digital highway).

It appears that either key authorisation is not being achieved OR the key barrel solenoid is not working. To achieve key authorisation requires an IR (Infrared) signal between the key and EIS and is powered by power from the EIS (not the remote batteries) by means of an inductance ring in the EIS.

Out of interest do you have the Easy Access function enabled (steering column goes up down automatically) and if so does this occur. If YES then I suspect the EIS lock barrel solenoid but if it doesn't then key authorisation would be higher on the list.

Now I do not know what MIGHT cause a key to go bad but presumably high magnetic conditions MAY do damage and this is why I believe the problem will be in the EIS (no power or lock solenoid failed) or possibly the coding which confirms the handshake between key and EIS. I don't THINK it is a CAN issue since the key won't turn.

You refer to a micro switch that senses key insertion? As far as I am aware the little spring loaded latches just inside the "key" aperture are to retain the key whilst in the ignition lock. No microswitch. Please tell me more.

Changing the EIS or "remarrying the key to the EIS" is an SDS Star Diagnostics routine so I still think this sort of issue is best dealt with by an initial SDS Quick Check (written report) followed by analysis of whatever the outcome of that test.

I'm mystified why everybody decides to change the batteries in the remote (particularly when the red LED on the remote still flashes when operated).

Anybody else able to add anything to this?

Good Luck.

Stuart

 

Oh,

Incidentally have you tried a reset. ESL Steering Lock can be reset by disconnect fuse or battery. Its worth a try.

Stuart

 

OK. I have a 2004 S430 4MATIC with EXACTLY the same problem. All remote functions work on the smartkey without any problem (door lock / unlock). Have tried both keys same behavior. Basically when you get inside the car and put the key in just won't turn. Basically is not recognized ... I have another Merc and it is like I am inserting the wrong key except I am NOT. After fiddling around with it for a few minutes ... it finally recognizes the key and "sucks it in" / clicks once and then I can turn it and start the car.

I live in michigan and it seems to be fairly well correlated with temperature. Have had the car for 4 years but started about a month or two ago... now with temps in 20's F outside... it happens EVERY time the car is out for an hour or two....

I am scared to take to the dealer cause of the various posts... seems like they go through a random list of replacements .. Help please. How can I know if my EIS needs to be replaced?