w21212pt

Hi guys!

My 2002 E-Class (one of the very last W210 models) has a problem with its key. Everything works very well except for the unlock button. It does not work at all. The red LED and the IR light don't light up at all when I press it. Everything else works. Any tips?

I already isolated the circuit board and tried to blow the dust off and do a gentle wipe with a soft cloth. Nothing changed.

Also, I need a replacement case for my key. Where is the best place to find one? (genuine). Can I retrofit the new style key from 2010 models (with metal sides) with the old circuit?

Thank you very much!

raymond g-

probably would help if you identify which Smartkey you have first. the only way you can purchase
an authentic key is from an MB authorized dealer or locksmith. that will cost between $2-300.
it may be possible to retrofit and repair your key for about $100 but it depends on the model

kajtek1

Suppose lately dealers asking in the range of $400 for chrome keys, so shop around.
One test of infra-red is to look at it via your phone camera. This way you will see if the beam is emitting, or not. We had a member fixing those keys, but did not see him around for quite some time.

Paulmurphy

Get a 10 times loop and check the micro switch on the offending button prob just needs a dab of solder

w21212pt

Thank you all for your feedback!

My key is the 2000-2006 model, same as the one on this picture (EU model without USA panic button).



The infra-red beam and the red LED always light up for the unlock and trunk buttons. Nothing happens when I press the unlock button though. This probably means that the problem comes from the button itself and not the full key.
It might be an easy fix without having to spend 350 euros (what they cost on official dealer where I live) for a new key.
@Paulmurphy What should I look for on the "damaged" button? Should it be coming loose or something? I have several remotes similar to this one. I might open them side by side and try to find visual differences in the electronic board.
I saw this topic on doing the retrofit from the old key into the newer style (2006-2009) chrome key. Anyone here has done it? Is it very hard?

kajtek1

You choose not to disclosure your location, but I know in Eastern Europe you can buy used key and have it programmed to your car for less than $100

Paulmurphy

Look directly at button through magnifier at the soldered joint if it is broken you will be able to move switch easily, repaired many of these before easy diy.