I've got both an '02 SLK320 and a '05 Crossfire and have put over 80K miles on each so I know what is normal and this is not. I am having trouble turning either of the keys for the SLK in the ignition. The trim ring on the dash around the ignition seams a little loose as well. I was told by a MB tech to get a new key but since the key I always use seams to work (or not work) just like the key that never gets used I'm reluctant to do that.
New ignition switch? Can the loose trim ring have anything to do with it?
Help!

The Tech is correct in his reply...Please try another key

I Have seen this several times and it the key

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The "trim ring" is actually the antenna to read the RFID chip in the key. It's only held in there with small plastic clips and can be popped out quite easily.

I experienced a similar problem in my '04 Crossfire Coupe (now sold). In a car that new, I can tell you what it's probably NOT going to be: The key or the tumbler. They are incredibly well made and will probably outlast the car itself. It's most likely the tab from the steering lock not disengaging completely. I was able to get around this problem for a long time by simply turning the steering wheel a bit to the left while trying to turn the key. It actually served as a low-tech theft deterrent system since if you didn't know "the trick," there was no way you were going to get the car started.

I made some pretty detailed posts of my experiences over at crossfireforum.org that may be helpful to you. Here's the link:

http://www.crossfireforum.org/forum/showthread.php?t=15839

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"It's not about how fast you can go, but how well you can go fast."

Bob in Richmond

'97 S320 (LWB), Ruby Red Metallic, 73k miles
'97 S420V, Smoke Silver Metallic, 155k miles

95% of the time that the key is difficult to turn at times is related to the tumbler.

Have it replaced. Should take less than 1/2 hour. Have the dealer special order that ASAP.


IF it locks up completely expect to pay $500-600 & wait several days.

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I had the same problem and got a new key today and the problem is fixed.

Question here... In my 1998 C230 lately the key has become particular about which way I put it in. If I put the buttons to the left it would start, but with the buttons to the right it would not start. Not it takes about 50 tries to get it to unlock and turn over, but once it turns over (cranks) it starts right up. Could this possibly be the "tumbler" and what is the tumbler? Is that the part you put the key into with the transmitter ring on it? How much does that cost?

Thanks

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra