[Solved] mercedes c200 w203 - the engine does not start and some devices in the cabin go

mercedes c200 w203 year 2000, petrol + gas (lovato), 163KM, "fish" key, the problems are as follows:
1.when the outside temperature is low, there is a problem with starting the car, the remote control opens all the doors, but with the second press of the remote control (here it regress because it opened after one press), after inserting the key into the ignition, all the icons on the desktop light up and I have to wait for them to flash and finally they will go out (it can take up to 30 minutes, the lower the temperature the longer), until the icons go out, I have nothing to dream about starting the car (it does not react) when it is warm (e.g. summer, there is no problem, it fires immediately) , I will add that when the car starts to react, a knocking is heard from the trunk and it matches the flashing icons on the desktop, after driving about 15-20 km, when the car warms up, I can put it out and start it like in the summer.
2.when it is wet (it is raining or raining or there is very high air humidity) while driving, the desktop goes out for 2s and turns back on, and it stops working for the same 2s: central locking, wipers and washer, turn signals, gear light reverse, horn, cabin light, air supply, air conditioning and window heating, I will add that the longer I go and the car heats up more the problem begins to disappear, I also have the impression that it has some connection with the amount of current in the system because the "short circuit" appears, for example at a speed of 50 km / h before the roundabout, I press the clutch to reduce the gear and slow down (revs drop and "short circuit"), with a hot engine after driving about 50-100 km, he took everything off with his hand.
3. only and only when problem 1 or 2 works, I found one more thing, after opening and closing the trunk, a message sometimes appears that I do not have the rear license plate light - which is a wrong message because the lighting is there and the bulbs are new.
The problems occur no matter what fuel I use, gas or petrol.
I am asking for help in indicating the place where to look and what to look for because now I can only enjoy car rides in the summer when it is not raining.

Search in electrical installation. Also check the masses.

I know it's an electrician, but I need a specific shot, I don't have time to do a full electric diagnosis because the car is used every day (me or my wife), sometimes I get out of the car and my wife gets in or vice versa, the masses are all checked (cleaned and reattached) , the car is under the "cloud", I bought it in the summer of 2017. problems appeared with the first rains and in the summer and later when the temperature began to drop below zero, so I am asking for a specific shot so as not to spend the helmet on an electrician, I will add that after the purchase I did not notice that the electric hook does not work (there were rotten wires at the hook module -I did), so I did not want to suggest, but I expect a similar option in other places, I just need to know where to look, and not run the meter all over the car.

You will not check with a meter, look for a 21 W bulb. I would start with the grommet in the tailgate, license plate light.

Jerry, thank you for the quick answer, but I am interested in solving 1 and 2 of the problem first of all, the stupid and incorrect message about the board will probably solve itself as I will fix 1 and 2, especially since not everything that is connected to one module, please help with problem 1 and 2, first of all, I will leave the general cargo for vacation (but in about half a year).

Hello, have you diagnosed problem # 2? Ie dimming the engine while driving.
best regards

pin in the trunk (broken cables) and a puncture on the ground in the fuse box in the trunk and under the hood at the front of the driver's door