Mercedes X Klasse Remote Issues

Sounds familiar. I had a similar issue with my Mercedes C Class. The symptoms were almost identical; the keyless entry became unreliable, and I even had trouble starting the car a couple of times. It was like the vehicle antenna wasn't picking up the key's signal consistently. Did you check the simple stuff like the car antenna fuse? Think of it like a garden hose; if there's a kink, the water (or in this case, the radio signal) won't flow properly.

Fuse, huh? I hadn't thought to check that. Whereabouts is the fm antenna fuse located? Is it easy enough to get to, or am I going to be contorting myself under the dash?

Well, my Mercedes isn't an X Klasse, so I am not totally sure about the fuse box location, but it should be detailed in the car's manual. If you are not confident, I would suggest going directly to the workshop; a defective cable or plug connection of the component is not difficult to find for someone equipped.

Cheers for the tip. I booked it in for the antenna repair. Turns out it was indeed a dodgy connector on the car antenna, just like you suspected. 95€ later, the central locking and starting issues are gone. I appreciate the advice!