A lot has been written on this site about this problem. I was having the problem of the key not turning, and having to try 6 or more times turning the steering wheel, etc. until it finally worked. I also read about others who were finally unable to turn the key at all, requiring a tow to the dealer and a bill for $1500.00 or more to fix. I want to thank Crossbow 39 for his nice thread on how to do this. I am a visual guy and thought I would take pictures and post a thread to help others. I also learned a few tips which may help others.

1.) Disconnect the negative battery terminal.

2.) Remove the fuse panel access door to the left of the steering wheel, in the door jam area.

3.) Remove the air vent above the headlight switch. It just pops out.

4.) Remove the lower trim panels. First remove the "U" shaped panel below the steering wheel (one screw). This gives you access to 2 hidden screws which need to be removed.


UPDATE
NEWEST PDF FILE AS OF JANUARY 9, 2021, is V6 - edited by OneHundred80.

ANOTHER UPDATE:
Robert McCubbin's version is shown as "Skicky Key Fix and Stuck Key Fix McCubbin V1.PDF see download links below.

 

5.) Next remove the one screw hidden behind the access door to the fuse panel, then the screws around the hood release lever.


6.) Next remove the two small screws securing the headlight switch/fuse panel assembly.

 

7.) Then remove the remaining 6 or 8 screws holding the lower panel, some are hidden in recesses.

8.) Gently pry down on the panel and it will pop down. If it doesn't you probably missed a screw somewhere.

9.) Next remove the transponder ring (chrome and rubber ring) surrounding the key hole. To do this press in on the back disc (escutcheon) and the transponder ring will pop out. It has a wire connected to it and can safely hang out of the way.

 

10.) Now insert your key and turn it to the right to the first click (position 1). Hold the key in this position and grab the black cylinder and rotate it counterclockwise about 90 degrees and the key tumblers will come out.

The steering lock assembly will now look like this. Next remove the electrical connector with two small wires (this is the key warning buzzer, the connector goes in either way). Then remove the parking interlock with the large black cable. This will require pinching the two black tabs at the rear of the connector.
11.) Now reach behind the assembly and you will feel the main electric harness connector. Pull and rock this toward the front of the car until it comes free.

 

12.) Remove the screw to the right of the key hole to free up the upper panel. This will allow you to pry up the upper panel for access to remove the lock assembly.

13.) Next loosen the strap clamp with the 10mm bolt holding the assembly.
14.) Then locate the locking pin which is hidden under a trim piece next to the steering column. If you pry with a screwdriver and use a flash light you will see it. Push in the silver locking pin and rotate the assembly counterclockwise and pull it to the right and its out!

 

15.) At this point you need to decide if you want to "modify" the assembly which means inactivating the locking pin or buy a new assembly. I bought a new one for $379.00.

16.) The assembly process is basically the reverse of removal but I did learn a few tips. The new assembly comes without the key warning sensor so you need to save and reuse the old one. It has a small locking pin making it difficult to slide out. I tried to lift the pin and slide it out with no success. Then I realized I didn't need to save the old assembly so I used a Dremel tool to cut the old housing and lift the assembly out. Then it slid into the new housing easily.

 

17.) When reinserting the key and black cylinder the flat on the black cylinder needs to line up with the white nylon portion of the assembly. Then you can push it in and rotate it clockwise to lock it in place.

18.) Also when reinstalling the transponder ring the part where the wire comes out needs to line up with the flat spot on the black cylinder for it to pop into place.
19.) Don't forget to replace the one screw you removed from the top panel (I did!) before replacing the lower panels.

20.) The front upper edge of the lower panel snaps into place, then lift the back edge (toward the front of the car) and secure one screw to hold it in place. Then just button up the rest!

Again I want to thank Crossbow 39 for his help. I think it has accurately been determined in this forum that this assembly is the problem, not just the tumblers, or lubrication. The only problem I have now is the BAS ESP light is on. Apparently when the battery is disconnected it sets the light. If you refer to page 135 of your manual it tells you how to reset ( re synchronize it)

 

Thanks for the detailed write up. When I changed out my battery, the same BAS ESP light remained on until I drove it up to about 20 mph, went out and never back on.

James

 

Fabulous photo guide!

Thank you.

 

Thanks for the write up!

So the cheapest way to do this would be to remove the original assembly and disable the locking pin (which is causing all this trouble). Correct?

 

So I still don't understand what the problem is for the 'sticky key' issue. Replacing the tumbler housing with the same thing will fix it for a while, and then back to square one? I am curious.

Thanks for all your info... James

 

Very well done!

Sticky!

Sticky!

 

Great write up I'll use it when mine finally gives out.

 

Just curious. If you don't get a new one. Which part do you exactly drill out and where? Can you mark it in the photo.

 

James, the symptom is a sticky key, that is you go to turn the key to start the car and it doesn't turn. Then you turn the steering wheel this way and that and finally after 10 attempts the key turns and your car starts! Others have thought it was just the tumblers, and/or lubrication of them. The real problem is in the steering lock mechanism housed inside the assembly I removed. Apparently a plastic cam inside wears down preventing the locking pin from retracting. The modification suggested by others eliminates the steering lock, so when the car is turned off and key is removed you can still turn the steering wheel. I decided to just replace the unit with a new one.

 

The modification done by others involves cutting off the locking pin which protrudes from the end of the assembly into the steering column. Do a search and you will find others who have done this. I decided to return the car to "factory condition" and just buy a new assembly. It will probably need it again in 5 years!

 

It is interesting that I had mine replaced last fall. With 17,000 miles on it and looking at the big picture, very few actual "turings of the key".
It almost seems that it isn't a wear issue as an evaporation issue.

 

Thanks. Does anybody have a picture of there's modified?

 

Fantastic write up and pic's! Many thanks.......hope I never have to use it but probably will!

 

Just a note i had someone come in last week looking for a lock cylinder housing. ours is $379.00 but if you buy it thru mercedes its $130.00 part #A2024600904. I lost the sale but helped a fellow crossfire owner........