I have a Pioneer AM/FM/CD player in my 1986 560 SEL. I chose the Pioneer for its superior AM reception as well as quality FM and CD performance. Lately I have noticed severe degradation in my AM signal. The FM works fine, still pulling in many stations. But the AM just doesn't seem to be getting the signal strength needed for quality listening. I have checked the connection to the antenna and everything seems to be clean and tight. I have noticed that occaisionally the power antenna hangs up while going from the fully up to the down position. Could this have something to do with the loss of AM signal strength? Possibly something internally breaking down inside the antenna shaft?

My guess is that the antenna isn't extending fully. Do a search on cleaning and lubricating the antenna shaft as a first step.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

Rockman59

I don't know if this applies to your radio but a lot of radios have trimmers where the AM can be fine tuned.

Check and see if this is true for yours. Sometimes these antenna trim adjustments are found oustide the radio, near the antenna connector.

Typically you tune the radio in AM to off-center of a station so that it is raspy sounding and then adjust the trimmer. The idea is to see improve the reception not using a well received station because you wouldn't be able to notice the difference.

Also check to make sure the antenna is securely attached to the body of the car, both at the base where it goes into the body and also at the bottom typically inside the trunk.

If the antenna mast is very dirty or the mast shaft is very dirty it can insolate it or reduce reception. A quick check is to use some WD40 on a rag and wipe the mast shaft repeatedly. If you get even a little improvement you are getting an indication of where the problem is.

Also you can take a piece of wire, say 3 feet, attach by hand one end to the extended antenna mast and see if your reception improves.

Keep us posted,

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

My guess is that the antenna isn't extending fully. Do a search on cleaning and lubricating the antenna shaft as a first step.
____________________________________________________

I have cleaned and lubed the antenna with WD-40 and it does appear to be extending fully and now goes all the way down to the full radio-off position. I have checked the base and wires and all appears to be in good condition. I do notice that when I touch the antenna with my hand when it is up the signal strength (volume) goes up considerably. Comments? Thanks for the input so far.