Key not recognised

[CLK CHAZ]

Hi
As above i keep getting the key not recognised mmessage and my key wont open the car or lock it.This is random and not all the time. Both keys are affected. Both have had new batteries.
Is it the key at fault or is there some sort of modual in the car that may be at fault. It always starts when the key is put in the ignition. sometimes it opens then sometimes not also the same with the locking. Keyless go workes and then not. Can anyone point me in the right direction and does anyone know any cost to fix.
Thankyou in advance
Chaz

 

[lxi]

I know it's an old thread, but this described my situation precisely - did you ever find out what was the problem?

 

[Petesnas]

I was just about to post something about this too!!....W209 CLK 55AMG here ......totally intermitent .....sometimes it works, sometimes not ....only starrted this weekend.....had one episode where i managed to open the car with the fob .....but then then tried the start button and 'key not recognised' ......quite a worry ........made my wife laugh though ...me standing in the pi**ing rain shouting at a my car keys

please help someone!!

snas

 

[GP801]

Had similar in the past with a W203. It was intermittent. At first dealer insisted it was the key at fault even though both were affected. It was something to do with the EIS and the security system. Most of it ended up being replaced. Fortunately it was still under warranty.

 

[BlackC55]

It is quite likely to be an ignition switch fault.

 

[lxi]

It is quite likely to be an ignition switch fault.

Assuming there will be multiple instances of something that can be labelled "ignition switch", could you clarify which and where for my benefit please?

 

[Petesnas]

It is quite likely to be an ignition switch fault.

mmm ...if this is the case .....is it an expensive/difficult fix?

 

[BlackC55]

About £600 ish.

I would get it diagnosed first before spending. I have seen two faulty keys also cause this fault amongst other things.

 

[lxi]

Tell you what - I'll take mine tomorrow to the local MB dealer, get it on Star & see what it says / what they say.

There are apparently several potential failure points in the keyless system so at least we will have one instance properly diagnosed - I will post back when suitably enlightened

 

[Petesnas]

I just called local MB dealer to get it stuck on a diagnostic machine .......they want £162 for doing it!!! .......surley there must be a cheaper way of getting it looked at? ...anyone know of anywhere in SE London (orpington way) that has the proper diagnostic kit, and is not going to rape me?

snas

 

[lxi]

well, took mine to MB dealership this morning armed with both keys.

They tried this, they tried that - the contrary b**stard behaved perfectly.

No faults (as in absolutely none whatsoever for anything) logged.

So, live with it I guess - I suppose there are more difficult challenges in life that pressing the unlock or lock buttons on the remote or putting the key in the ignition slot and turning.

 

[jimmymidnight]

I had this issue with my CL500, firstly it was a problem with the door handle of all things, I had it repaired under warranty and it worked fine for about 4 months, then one day it just didn't recognise the card any more so I took it to a specialist a few villages over and they said it was an ECU issue and it would cost about £600 to fix, so now I just turn the key like everyone else. I will probably get it fixed again at some point, but im no rush to spend the money on that. My dad's SL500 broke 3 times and every time the dealer said it was a different issue so wasn't under the original labour warranty...