Audio Systems/need help plz

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Question
hello
thank you for you help to other people like my self who ask you for help.
my problem is that my AM stations on my car stereo don't work but my FM stations do and i do not know why?
i have a Volkswagen Golf year 2000.
i did check my radio grounding and it is fine and my antana looks fine too. I even changed my stereo just to be sure and the same thing it's happening .I'm confused because i do receive FM station but not AM station. from your experience what you think the problem could be? i do highly appreciate your time to check this email.
                                     Thank you

Answer
Assuming the head unit is working properly and you are getting good FM reception the loss of AM is almost always an antenna connection or antenna feed cable related problem.  

Here is a way to check it:

ONE: Pull the unit out of the dash if you have an external antenna and try it directly.

TWO: Or, if you don't have another antenna you can still pull the unit out of the dash and fire it up using a length of single strand wire.  Strip one end of the insulation off the wire and insert it directly into the antenna input jack on the back of the radio.  This will act as a dummy antenna and a wire a few feet long will tell you if the radio AM section is working properly.  Then you will know it is something to do with the antenna connections.

A good ground on the antenna is important and some cars have an AM amplifier at the antenna or somewhere in the car that requires a connection to battery to provide power for the signal booster amp.  Volkswagen uses booster amps on the antenna on many models.  So, check that out. Look for  a wire that has not been connected yet....

Hope these ideas can get you on the road again.

C  

Audio Systems

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Cleggsan

Expertise

Audio Design Engineer; systems, loudspeakers, cd/dvd players, etc. I am knowledgeable in all high end audio equipment and installations. MAKE SURE YOU GIVE A MAKE AND MODEL NUMBER AND CAR IF IT IS AN AUTO QUESTION. Note: I am getting some who ask good questions that take a lot of time to research but then the questioner fails to read the answer. Please don't ask questions unless you are seriously looking for an answer. If you find an answer to your question otherwise then let me know with your reply. Thank you.

Experience

Have been associated with audio design, standards, testing and component systems for over 40 years.

Organizations
Life Fellow Member of Audio Engineering Society Life Senior Member of Institute of Electronic and Electrical Engineers

Publications
Review technical manuscripts for IEEE Spectrum Write occasionally for high-end audio publications

Education/Credentials
BSEE/MSCS/MBA

Past/Present Clients
Past Employee/advisor to several well known audio products manufacturers

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