Key fob again

[alec2]

Thank you all for advice earlier in the week i am now keeping my eye on e-bay for a replacement housing for the electronics.

But some questions.

1
I presume the RF bit is limited to opening the door locks and activating the alarms (plus some other bits and bobs if special features are fitted).

2.
Why then, is there a IR feature as well?

3.
Is there yet another feature which enables the key to turn in the ignition switch and lets the engine start?

Mercedes tell me that you cannot reprogramme a key for a different car, if so what does the programming info available on e-bay do? perhaps it just reassociates the RF stuff if the battery has run down

Alec

 

[Blobcat]

Depending upon the car the RF will lock and unlock the doors and open the boot

IR will if your close enough to the receivers open and close the windows and sunroof if you hold down the open or close button

IR also disables the immobiliser when the key is put into the ignition

 

[television]

Thank you all for advice earlier in the week i am now keeping my eye on e-bay for a replacement housing for the electronics.

But some questions.

1
I presume the RF bit is limited to opening the door locks and activating the alarms (plus some other bits and bobs if special features are fitted).

2.
Why then, is there a IR feature as well?

3.
Is there yet another feature which enables the key to turn in the ignition switch and lets the engine start?

Mercedes tell me that you cannot reprogramme a key for a different car, if so what does the programming info available on e-bay do? perhaps it just reassociates the RF stuff if the battery has run down

Alec

You do not get both RF and IR,your car is one or the other, a rough guide being cars from 2000 are IR, Rf has a much longer range the IR

The key has a transponder that matches the DAS of the car, that is why only the correct key can be used.


Malcolm

 

[television]

A little more info for you.
Drive authorization is independent of the security status of the radio remote control or infra red remote control and the batteries in the transmitter key.

Drive authorization (DAS) is enabled by the secret data exchange between vehicle key,electronic ignition switch control and engine control module.

in other words the remote part of the fob can be U/S but the key will still work.

In my earlier piece i said that you cant have both RF and IR, this stands.

Some confusion may arise in some hand books around 2000 when the change over took place and your book may refer to both. One should not forget that IR can be sent a fair distance and around corners by bouncing it off things.

Have a play with your TV remote (IR) and bounce the signals off things in the room.

Malcolm

 

[eric242340]

The central locking and ignition part of this key sytem are completely different. For ignition - DAS is the programme and can only be programmed by mercedes Benz dealers using a green key. This is a smart key that can code the EIS (Electronic Ignition Switch) Central locking is an indepenant programme. Central locking is quite a simple programme, however DAS is a complex security variant coding. I havent found anyone who can crack this code yet.

 

[television]

DAS is a complex security variant coding. I havent found anyone who can crack this code yet.

There are at least 4 companies that make Key programers, sadly our cars are not included in the list.

The pictures show the inside of a 210 IES ignition switch, no less than 15 IC's 3 of them are of the 80 pin variety

The large coil round the key entry is the transponder coil that picks up the info in the key, on inserting this key the data is passed to the DAS and with luck your car should start. When this piece fails you will need £410 for a new one.

Malcolm

 

[eric242340]

Also on this system is DAS, Drive Authorisation System - this system meets the security requirments of both EIS< DAS< and central locking, but without the correct test equipment you havent got a hope of fixing it.

 

[television]

Just one more thing. the circuit of this complex switch in my above answer does require 12volts and draws current,this is coupled and driven from a SAM module. A SAM module is used to keep things on hold as it has a very low current consumption in the sleep mode. When you open the car door the SAM wakes up and energizes the IES module and other components, enabling you to drive away.

Malcolm

 

[television]

Also on this system is DAS, Drive Authorisation System - this system meets the security requirments of both EIS< DAS< and central locking, but without the correct test equipment you havent got a hope of fixing it.

I can repair most modules, and control units, but not this one.


Malcolm

 

[television]

I should at this point say thank you to Malcolm 210 for the loan of his faulty IES switch that i was able to photograph and put up here.

Malcolm 210, would you like me to return it to you.

Malcolm

 

[alec2]

Thanks for all the replies which confirm much of what I thought.

1. The RF just unlocks the car and deals with the alarms

2. There is a separate system to deal with the ignition features ( probably RFID technology)

3. But I seem to have IR as well through a sensor in the Door handle!

Alec

 

[television]

Thanks for all the replies which confirm much of what I thought.

1. The RF just unlocks the car and deals with the alarms

2. There is a separate system to deal with the ignition features ( probably RFID technology)

3. But I seem to have IR as well through a sensor in the Door handle!

Alec

No,you have one or the other,not both. to check what you have,take a digital camara and point the fob to the lenz, when the button is pressed if you get the flashing light in the camara,its IR.

Malcolm

 

[alec2]

Yes I do get a flashing light, and there is a small sensor window in the door handle Perhaps this only works the window trick?

I consider that the main locking is RF as I do not have to have the car visible to get it to work.

Alec

 

[television]

Yes I do get a flashing light, and there is a small sensor window in the door handle Perhaps this only works the window trick?

I consider that the main locking is RF as I do not have to have the car visible to get it to work.

Alec

You have not read all of the answers. You do not have RF its all IR,you can bounce IR off walls doors any hard surface. You can turn your Sky box on through a glass door.

Malcolm

 

[ba9rn]

Yes, I am sure that (like me) you do have both. No idea why they provide both, but the car will lock/unlock without any line of sight - bounced or otherwise (it must be RF). The window open/close does require pointing the fob at the driver's door handle (must be IR).

Malcolm - mine works in my pocket, inside my house, etc. (no windows involved!). It is certainly RF - I doubt whether the window open/close 'trick' is RF because that only works with the fob in fairly close proximity to the small receiver window in the driver's door handle.

 

[Ultymate]

I have a C230K estate and that has both RF and IR Malcolm there's just the one IR receiver on the driver's door handle

 

[dursleyman]

We have 2001 C200K Avantgarde that has suddenly developed a problem with unlocking. It only happens if the car has been left for a while, such as overnight. We obviously suspected the key fobs so the dealer replaced the batteries in both but the problem still persists.
Most mornings we can spend about 10 minutes walking round the car pressing the fobs like idiots until it finally unlocks. Very frustrating.
Any ideas please?

 

[Blobcat]

Attached are two photographs I took today, the first is of a button press on my Yr 2000 W210 key and the resultant spike at ~433Mhz on a Spectrum Analyser. The second is a close up of the screen of the Spectrum Analyser.

 

[television]

I will no longer take part in this thread.

I will no longer take part in this thread as a posting has been changed. and that has an unfair advantage over what i can do.
I just feel ill when I read it all, sorry folks.

Malcolm

 

[ba9rn]

:sad: Sorry if my edited post has caused you pain. It was just meant to illustrate that I do have both IR and RF in my fob. I still don't understand why I need both however.