antoniyo1593

Hi guys i have an issue with my s203

my fob is not lockong or unlocking it does working because the light flashes when buttons pressed. Nothing happens when key is insterted into the ignition..

slammer111

Have you tried the other key fob?

If the other fob works, your EIS is broken. If the car starts, the key fob is broken.

an6dk

I have had this issue and it was one of two different things for me. Because you know your key works then your issue is with the IR receiver in the door handle. The solder used in these cars has a tendency to make bad connections because if I recall it was lead free per some EU regulation. Youll need to pull the piece of the handle the sensor is in out of the door to get to it and repair it. To do this you just have to remove one screw directly behind it which you can get too by pulling off the door gasket/weather seal rubber thing and looking for a hole behind that part of the handle. You should be able to see the screw if you bend down to look into the hole (t25 I think) after you unscrew that (dont worry about getting it out, its a captured screw so you cant loose it or take it out) you can pull the part of the handle the sensor is in out of the door, your handle may come loose but it isnt an issue and you can put it back where it belongs before you put it all back together.

now that youve got the sensor assembly out youll need to pull the sensor itself out of the piece of your handle to get to the problem solder joint. Once you have it out you need to scrape out all the epoxy in the sensor so you can visually inspect all the solder joints for a bad connection. Just resolder any connections that look suspect and you should be good to go, feel free to refill the cavity with an epoxy if youd like. I didnt because I didnt think it was needed. Now the IR remote will work as normal. If the remote still doesnt work well you may have a broken radio receiver antenna that recieves the long range unlock signal, in that case Im not aware of any fixes that are really worth the time/money you have to invest for them.

an6dk

he didnt technically say it doesnt start but if it didnt then I wonder if the little chip in his fob that contains the car specific info is cooked. These cars are car unique if I remember (as in you can make a new key and its the car itself that has parts that cant be replaced) so maybe a replacement key would fix it

Lou B

From my own similar experiences several times, it is possibly a good time to put fresh batteries in each fob. Flashes occur even when the battery is weak.

an6dk

I second that, making sure the contacts are clean is also a good idea when you swap the batteries because mine stopped working due to a contact not being firm enough