C240 mercedes wont start. after backing into a parking spot?

Your brake light switch is not working properly, preventing the interlock from releasing the shift lever. I'm linking a YouTube video showing how to release the lock manually. The person who did this video dismantles the console to show where the lock is located, but you don't have to do this if you follow the initial guidance on where to aim the tool to depress the button.
Mercedes W203 STUCK IN PARK How to put in Drive c180 c200 c230 c240 C270...

Brake ON and shift gear lever to N - neutral and try to start.

It can be a bad neutral safety switch.

Go to Advance Auto or Auto Zone and ask them to read the error codes. Then lookup those codes on the Internet or post them on https://mbworld.org/

model: 2001 C240 problem: wiper blades "park" almost in the middle of a windshiled when turned off. When wiper blades are on they cover complete range of a windshiled.

My Mercedes C-Class 1996 won't start up, the alarm is confused it thinks it's locked, every time i unlock it, the red light( locked) and green light(unlocked) flash at the same time constantly, if I open the car and try turn on the engine, the alarm starts blaring, I've turned it on before and drove it around but when i came to park it up it did not turn on again because of that problem.( The car hasn't been touched or used for a year before i got it going again)

I have a 2001 C240 with the same issue. I removed the positive battery cable from the battery and kept it off for 30 seconds then replaced it. Everything was reset and the key worked.

Yup, either NO fuel or NO spark !!

I am assuming that the engine won't even turn over. could be lots of different things. The simplist is to make sure the car in in PARK , won't start if not. Other things could be , Security imobilizer if you have one. Does your key have a electronic chip in it ? Try your other set of keys if you have one. Check if battery connections are clean and tight.

a/c control unit or low refrigerant pressure-leak in system,find leak and get it fixed,dirty oily spots on a/c lines or at sealing points