[Solved] Mercedes CW 203 - Key Issue at -15 Degrees: Ignition Not Reading Key, Remote Control Inconsistency

Hello
I have a problem with the key "Rybka" I did not have problems with the key until the frost came -15 degrees (maybe just a coincidence) since then it happened to me that the ignition did not read the key. When I took it out and put it in a few times, it read it and it was okay for a while. After a few days, the situation reappeared, but again when I took it out a few times and put it in it was okay, but today for an hour and a half there was no reaction, the remote control could be opened and the door closed, but when I put it in the ignition there was no reaction. When I finally got it started and I got home, the ignition was reading the key near the house. After a 5/6 hour break when I wanted to start the car again, the ignition did not read the key for a long time I tried to start it but nothing helped. The pilot once worked and once it didn't. I checked all the fuses and they are ok. Do you have any idea what could be the reason? I will add that the key was made and I had no problem with it for 3 months. The above situation began to happen when the frost came


the car is a Mercedes C class W 203 from 2002. 2.0 petrol 130 km

Start by replacing the battery, if that doesn't work you need to check the coil in the key. Often when the key falls, the winding is broken. Then the ignition does not respond to the key, and the door opens normally.

Of course, there is no spare key - for what, if this one works (worked). When it is frost, the FBS switches usually kneel. Heat it with a dryer - the ignition will blame as the key.

I gave the key to check. It turned out that there was some error on the circuit board and because of that sometimes the ignition did not see the key. They fixed it in the form of a guarantee. We will see what the effects will be after the exchange

Two days after the repair, the problem appeared again ....

Heat the ignition switch. How to light skeins in ezs for exchange. And do it quickly as long as it can be read because later it will be more expensive.

I noticed that in the old key from the remote control power supply the battery was damaged (scratched, broken) and that was the reason for repairing the key because the remote control did not work for me. After repairing the remote control it worked, everything was ok until the above mentioned problems started to happen. But recently when this situation took place again I took out the batteries from the remote control and suddenly everything started to work normally.

And what does the battery for the ignition switch have?

Welcome back,
so the problem in my case was the processor on the circuit board in the key.
the processor had microcracks, which meant that when it was in a warm place the key worked and when
the processor got cold again and he refused to obey.
I dismantled the ignition and drove it to the service site to make new keys for me ever since
I don't have any problems with the key
repair cost about PLN 1000 for two completely new keys + some time taken for disassembly and reuse
key switch assembly.
thanks for the help
Regards