I'm having a tough time figuring out the source of radio noise in my 1997 S500. With the key in the number 1, or accessory position, the radio, C/D and cassette all work perfectly, but when the key is in the number 2, or run position, I have very bad noise with the radio bands even though the C/D and cassette still work perfectly. This happens whether the engine is running or not.
I have 2 factory radios and a new after market radio. All 3 have the same symptoms.
I also installed a new Hirschmann universal antenna but it made no difference.
I was wandering around on ebay looking at used amps but found a part called an "antenna amplifier noise supressor" listed and wondered if that could be the problem. Here's the listing:
Mercedes W140 S320 98 99 Antenna Amplifier Noise Suppressor 1408202189 21048 | eBay
Does anyone know where this part is located in the car?
Thanks, Bob Short