98 E320 remote distance question.

[Paul_Dierze]

Hi The remote for my 98 e320 only works within say 10 feet of the car. I've replaced remote batteries with no increase in range. Both remotes are about the same.

Is this typical? And if not, is there a DIY solution?

[Ed Richardson]

That is about right. For security reasons it is an infrared system, not radio signals. The sender needs to be aimed at, and have a clear shot at the receiver points.
Ed

[BENZ-LGB]

Originally Posted by Ed Richardson

That is about right. For security reasons it is an infrared system, not radio signals. The sender needs to be aimed at, and have a clear shot at the receiver points.
Ed

Yep, what he said.

Although in my C320 wagon the range seems to be far greater.

[Paul_Dierze]

Thanks, Not the answer I was hoping for But I'm glad to put it to rest.

[ILUVMILS]

If your car is a 1998 model it should have radio frequency locking. The easiest way to tell the difference is to check which type of key you've got. The older IR systems use a folding metal key while the newer RF systems use the infamous "smartkey".

[Ed Richardson]

That is new to me. Are the "smartkeys" totally RF, or just the locking?
Ed

[BENZ-LGB]

Originally Posted by Paul_Dierze

Thanks, Not the answer I was hoping for But I'm glad to put it to rest.

This is not a "solution" per se. But if you press the key against your chin, it increases the range.

It looks stupid as hell, but it works.

I have the smartkey, not the switchblade one.

[raymond~]

Smarkey....and, if you extend the sliding metal key and touch it to your chin/
jaw, the range will extend another several steps.

Smartkey alone, casual use for my 99 E320 is about 60'. Using chin method is
80'. With metal key-to-chin method, 100'.

[ILUVMILS]

Originally Posted by Ed Richardson

That is new to me. Are the "smartkeys" totally RF, or just the locking?
Ed

Smartkeys have both RF and IR capability. The RF signal can lock, unlock, or open the trunk. The panic alarm can also be activated via RF.

The IR function of the key is different. In addition to locking and unlocking, the convenience feature can be used in IR mode. If you look at the exterior handles on your front doors you'll see a small "window". If the key is aimed at one of these windows, and the unlock button is pressed and held, the car will unlock and the windows and sunroof will open. The reverse will occur if the locking button is pressed and held. For this feature to work though, you'll need to be within a few feet of the car. This is a nice feature to have during the warmer months. In fact, it's now known as "summer opening".

The other IR function takes place when the key is inserted into the ignition switch. The rolling codes programmed into the key are read by EIS via IR. This is how the Drive Authorization System determines the correct key is being used. The key is powered inductively by EIS, so if the key batteries are dead the car can still be started. I hope this answers your question.

[Ed Richardson]

Your answers are really appreciated, however, the electronic age in me is still lacking. I am very familiar with the IR keys, but not these guys. Do the IR and RF both work together redundantly, or do they each have their own function,
i.e., why the RF?
Thanks again
Ed

[raymond~]

http://mb.braingears.com/W210/w210/electrical_rclatapse.htm

[Ed Richardson]

That is great Raymond, thank you.
Ed