Why would the car remote stop functioning AT THE EXACT SAME TIME that AM radio intereference starts? At first both would function fine all day until it got hot outside - then both would go wrong. now it both problems occur all the time.
My guess is there is something creating interference that you pick up on the radio and coincidentally prevents the remote from working. It is possible that by driving closer to the source will cause the interference to intensify as a means to try and locate it.
Something inside or outside of the car is generating radio interference and this “buzz” is blocking out the signal from the remote…They make R/F sniffers, used to find electronic bugs and surveillance equipment that could be used to find the source of the interference in your car…
I’d be hesitatnt to make any assumptions that the two problems are connected until I tried changing the battery on the remote. Contrary to what the TV shows say, there ARE comincidences!
I bet it is a utility pole that has a bad contact somewhere.
Here’s an old sparky trick to find the offender:
It requires one AM radio and one large sledge hammer.
Drive around with that AM radio on and see where it gets strongest. Find the nearest utility pole, get out of the car and give it a good whack at the base of it with the sledgehammer.
If the interference stops, that’s the pole that has a bad connection up there.
eport it to the utility company but do not divulge your method for finding it. They may frown on it.
@WesternRoadtripper, It is an old hamster trick - most hams that were into it in the day own a sledge very likely for that very reason.
Years ago, a friend of mine and I were into weak signal radio where one can’t afford to have too much background noise when you’re trying to contact Japan with 2 watts HF or bounce VHF signals during auroral openings.
We would drive around in a pickup truck, wearing hard hats, color coordinate with orange shirts and sport at least one clip board. The trick is to look like you belong and know what you’re doing.
The ECM uses some oscillators in it and I suspect that either the shield on the ECM has lost ground or there is a shielded wire from the ECM that has a broken shield. Is it possible that you have installed an inverter to supply 110VAC to power/charge a laptop?