AM Radio Reception problems

Hi,

I have a 1995 Saab 900S with the factory installed Clarion AM/FM/Cassette Radio with 6 CD changer in the trunk.

All seems to work pretty well except for the AM radio reception which has been horrid from Day 1. Dealer has replace parts of the antenna and leads, etc. but the problem -- lots of static where the stations should be -- comes back.

For whatever reason, the only constant is that the AM radio reception actually improves noticeably when I have the brakes depressed and/or with the rear window defogger on.

Any thoughts or ideas?

Thanks.

fred.r

Reply to
freddotr
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Not my area of expertise, but I've seen posts from others who cured A.M. static by cleaning and reattaching the ground wire.

Reply to
Skid

Where is this wire and how do you access it? Anything is worth a try. Two Saab dealers have failed to make the AM work normally on my '95 900S; one suggested "rewiring the car" . I walked out of his service department laughing out loud.

Mike Yankee

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Reply to
MikeYankee

Mike,

I haven't had a problem, so I'm just repeating what I've read here and elsewhere. But I have seen lots of complaints and suggested cures in the forums at

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A search for "AM" "RADIO" or "STATIC" will get you lots of hits and a few clues. Here's one sample checklist:

1) Clean the battery terminals and the major grounds at the radiator crossmember and trans cover are shiny bright.

2) Check that the short alternator ground wire from the alternator to the alternator bracket. Clean and tighten. The allen screw that holds it to the bracket likes to back out.

3) Unplug antenna connectors at antenna and behind radio DIN box. Check that there is no continuity between center conductor and outside of plugs or between ground and same. If so the coax cable is shot. When you have the radio out, spray some electrical contact cleaner on the connectors between the back of the radio and the DIN box and scrape any corrosion off the connectors with a dental tool or a small screwdriver.

4) Spray some penetrant into the base of the antenna. The collar gets rusted to the antenna housing. Clean the antenna with contact cleaner(not oil, which attracts dirt).

5) Loosen antenna motor bracket screws and turn on radio to to extend antenna to make sure that the bracket is down hard against the body. then retighten the screws with the antenna up. Check the ground wire at the electic antenna and maybe add an exta ground wire here to a ground under the back seat.

6) Make sure that you have a suppressor capacitor between the primary side of the coil and ground and that the wires are not broken. This is a Saab part and mounts on the coil bolt and normally grounds to the side of the distributor. Use a non-digital ohmmeter between the connectors and you should see an initial low resistance that quickly increases up as the capacitor charges. If the capacitor is missing, you cannot connect a Radio Shack feed-through capacitor between the coil and ground or you will blow the ignition fuse. If you use one of these capacitors, you must connect the coil to one of the terminals and ground the body of the capacitor with the coil bolt, and it's a good idea to tape over the other terminal so that it is not accidentally grounded.

7)Bougicord wires with non resistor NGK plugs are best and make sure that your rotor and cap are in good shape(rotor should have about 1k ohms resistance between the center contact and the tip) El cheapo rotors will show zero resistance and make noise and cause poor performance. Resistor plugs may prematurely burnout your rotor.

8) If you check all of the above you should be in good shape. If still not satisfied add a noise filter from Radio Shack to the radio power supply.

This is the kind of stuff that's relatively simple but time-consuming.

Good luck,

Skid

Reply to
Skid

Try putting a filter in the antenna line. They'r available here in the US at Radio Shack. There are two types of filters-one for the power and one for the antenna-get the antenna because the fact that you have noise only on AM inticates it's the antenna. Phil Brown

Reply to
Phil Brown

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