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Ignition switch sometimes doesn't recognizes remote key
I have a reserve key but with no remote function do I must take with me two key (I have only two) when I want to start my car, Fist key to unlock remotely the car and the second to start the car.
So please can you help me?
Must I synchronize the remote key, and if HOW?
thanx in advance
If the key is dropped this coil can break off, I get keys from Ebay and change them.
On the longer type key there is a coil on the end and the wire on the end can break where it is soldered on, giving an intermittent operation, these can be soldered up.
Very often though this intermittent operation can be signs that the EIS ignition switch is failing.
This is of course very disappointing. Keyless-GO is largely useless. It would be very useful if I could keep it in my laptop bag and not have to guess whether it is going to work or not.
Now that I am hearing that the same (or similar) problem persists in newer models, it may be the time for a Dear John (Dear Benz?) letter. If I only had the time.
I enjoy the CL600 the most without these gimmicks (no radio, no navigation). It is designed to be driven. With a key.
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Many days later (with the non-MB dealer sorting out other issues with the car) and many reads of these forums later - including in-depth analyses by Television (member who has posted earlier in this thread) over a number of years - I came to the conclusion that I will have a play with the key. I have this car as a holiday car and so not normally in a hurry to get things sorted out quickly.
The key (in layman lingo)!
As explained above by others, the key is 'energised' by the ignition system via a coil inside the key. The charge is enough to get the key to transmit its various codes to the ignition module and thereby the resulting chh-ching and steering unlock and start.
Now, firstly, if it doesn't work properly in the ignition BUT the other key does (flat, emergency key or any of the others), the problem is very likely to be with the key and not the ignition.
Here are actual observations:
1. Took out the key electronic board from the fob and noticed coil was broken. Had an old emergency key (from a 98 E280) which I cut open and it had a similar coil. Paid a satellite repair shop a tenner and the guy soldered (With Care!) the newfound coil onto the key.
2. Tried key in ignition. No luck. Tried many times to insert/ remove/ jiggle whilst inserted.. the usual - and it eventually gave! The key turned and the steering was unlocked. Got to ignition, turn - but no engine turn!
Conclusion 1: It does the code transmission TWICE - once in pos 0 and then again in pos 2. (Anyone confirm/contradict?)
3. Back inside the key. Cleaned the inside of the red lens. Cleaned the red lens on the ignition entry. Key in - steering unlocked - starter engaged - ignition! Yeaheh! Tried it again - nope.
4. Clean only the ignition end again.. works! And since then, whenever the key misbehaves, I just clean the lens on the ignition entry. How? By very simply wiping the lens with my fingertip. Initially I'd do the full drill - get a clean tissue, not too much water on it, just a light swipe, etc. Then I noticed it would work with even a very Very slightly wet fingertip (tongue). Then I saw it didn't even need that. A dry fingertip works too.
Conclusion 2: I think the coil/ ignition 'energising' can become weak because of something on the key board - maybe even the coil itself. It shows more (ie malfunctions) on the fobs only because the fobs are much thicker than the emergency key. The red lens is, I believe, supposed to help out, but the red lens can lose its clarity, and if its marked/ scratched, probably loses its clarity very quickly if dirty. The cleaning helps the clarity and the weak current gets through enough. (Again, anyone?)
If you have to get into the key, the inside looks like the picture posted earlier in this thread, although the coil may be a different shape. Open with care (there are details about it in one of the MB forums - googling ought to get you to them, I don't have the references to hand). You'll need a small screw driver to pry the white plastic latch inside the fob so that the key board can slip out.
unfortunately not, I tried cleaning exercise, but this doesn't help, I am now trying to open the key but I don't know on which side should I put the screw driver to pry the white plastic latch inside, when the key is lying so that the (buttons are down and the Mercedes logo is up) where should I put my screw driver above the white plastic or under the white plastic?
There's a description of the process in the link below and a useful pic too.
http://forums.mercedesclub.org.uk/sh...ad.php?t=50294
I marked those wires on a coil with red rings, could it be that this indicates that the coil
is broken?
I marked those wires on a coil with red rings, could it be that this indicates that the coil
is broken?
Just a word of caution - if the key works intermittently it may not necessarily be the coil. Otherwise, if you are capable of soldering it back onto the board, remove it so you can inspect it closer. If you need another coil, get a similar key off ebay so you can take it apart and take its coil.
But - if you have a digital board repairer/ satellite & TV repairer nearby - you could get them to check the coil for you. This way you'll be more confident that the coil needs replacing.
All else failing, you could always get a professional keyfob repairer to do a complete check on your key. They would check all circuits and replace the coil if necessary. Its about 30% of the cost of a key from the dealer here in the UK - I don't know if this service is readily available your end.
I am thinking to bug this key
http://www.ebay.de/itm/ws/eBayISAPI....634243020.html
I am thinking to bug this key
http://www.ebay.de/itm/ws/eBayISAPI....634243020.html
Best of luck! I suppose its worth a try for 15 Euro.




