dfrois

Well, here is my first call for help/guidance.
I bought a 2003 CLK270Cdi with issues, a few weeks ago. I have solved some, but am now at a loss with this one.
Car came with two keyfobs. Both start the car on the ignition. None works in RF (probably busted antenna amp). Here's the issue: one of them works via IR, on the driver's door. The other one lights the LED, emmits IR (checked with phone camera), starts the car, but I cannot sync it to work via RF on the driver's door.
I checked the PCB visually, and no damage. New batteries, LED lights, IR emits, but no joy. Tried syncing it with following procedure:

-Insert key in ignition
-Turn on ignition
- Remove key
- Within 10 seconds, press "unlock", keep it pressed, and press "lock" 5 times in arow, quickly
- press any other key

No joy. Any idea what could it be?

It is the spare key, but still, would like to have it work normally. I intend to replace the antenna amp, to have RF working, but this second fob not working in IR probably means it will not work in RF, even if the system is OK...

Any suggestions?

Thanks.

dfrois

Obviously, I meant "...but I cannot sync it to work via IR on the driver's door...", not RF. Sorry.