Poor Radio Reception

[LenO]

The radio reception in my 04TT is poor. The FM is disappointing and the AM is dismal. I've complained to my dealer with no results. Has anyone tried any antenna modifications or changes in the rear spoiler? Are there separate antennas and amps for FM and AM? How about adding an additional amp? How about increasing the size of the antennas or possibly just repositioning them in the spoiler? Is adding an external antenna to the top of the spoiler an option? I have to many questions and no answers. Any help would be greatly appreciated.

[Bostonduce]

Len;

Any mods to the factory MOST radio are difficult because of compatability, if that's what you mean by adding "amps"

However if you mean antenna amplifiers, I've used antenna boosters by a company called Antenna Specialists. You power a small (about the size of a pack of cigarettes)electronic module and plug it in series with the antenna lead.

Unplug the antenna lead at the radio plug the antenna feed into the A/S unit and then plug the lead on the A/S unit into the radio.

Unfortunately, although I've installed them in a P car, it was not a 996. I'm unsure if they are still around, but they used to make both an FM only and an AM/FM booster.

One word of caution, if the receiver is really that weak, when you boost the signal (especially AM) you tend to get a lot of cross channel interference and static in general.

Try Crutchfield for auto radio accessories.

Regards,

BD

[wingless]

The radio antennas already have amplifiers. Perhaps the fuse is blown or they're defective.

[LenO]

Thanks for your responses. Yes, I was considering an antenna amplifier. I am aware of the Antenna Specialist amps. I have an old FM version. A/S was absorbed by a larger company and no longer has the same product line. There are other brands available though. I am receiving AM broadcasts but the weaker station reception is no where near that of my wife's Lexus or any other car I have owned for that matter. The Porsche amp is probably working, just not very well, so I don't think it is just a fuse. It could be a defective amp but I have not yet been able to get the dealer to go that far yet. I have also noticed that the AM reception was just as bad in the S the dealer gave me as a loner. I was curious about the size and type of AM antenna in the spoiler. I was wondering if it could be augmented or modified to improve reception. If I did try the antenna amp, I was thinking of adding it at the spoiler end to boost the signal before it went into the Porsche amp. Any ideas are greatly appreciated.

[LenO]

I thought I would get more specific about this radio problem I'm having in my 04TT. Maybe this added information will get a response from the electronics experts.

1. The problem only occurs during AM radio reception.

2. With the key in the "Initial position", the PCM comes on and AM reception is clear and strong.

3. When the key is moved to the "Ignition on" position (no engine start), there is white noise, or a loud hiss added to the AM reception.

4. The weaker the AM station, the more pronounced the noise. It is present even for the stronger stations, but not as prominent.

5. There is no problem in FM or CD modes.

The noise is obviously being introduced by the vehicle electronics. There should be a noise fillter or supressor somewhere in the system to prevent this problem. Does anyone have any ideas?

[mudman2]

I would say that you have a problem in the diversity system, some ground connection allowing pickup from car electronics. OR one of the connections (2) on the back of the PCM have come off.

My bet is the PCM connectors. Pictures on my rennlist gallery

[LenO]

Thanks Mudman2. I agree that electronics noise is somehow getting in where it shouldn't. I checked out your pictures at your Rennlist gallery. Good info. I was wondering how I could get the PCM out. My PCM is working 100% except for the AM noise. When you suggested one of the connectors could be off, are you talking about a ground connection? Looking at your photo of the back of the chassis, there isn't much there. Any connector that was totally out would cause some function to be missing. The antenna shields should be grounded through the antenna jacks. Is there a chassis ground connector or is it just grounded through the mounting screws? The power connector should have a negative side. Which one is the power connector? I have to find one of those hook tools before I can operate. Thanks for giving me something to work with.

[mudman2]

Not the ground which would effect everything, more likely the antenna connectors not on right, this could happen in manufacture as they pushed it in. These are weird little things which once on properly should stay but having played witht them I can see why it might happen.

[LenO]

I've been following Mudman2's advice in pursuit of my problem. Checked connections at the rear of the PCM and in the spoiler. Everything was good and clean. Went to the dealer and checked reception side by side with an 05TT and the noise on my system was significantly higher. He checked all connections again and replaced both diversity antenna modules in the spoiler. No improvement. On the 60 mile trip home I took a country road instead of main highway. I noticed that every time I went through a depression in the road the noise level on the radio pulsed up. I have been running with the PASM in the "COMFORT" setting. I switched to the "SPORT" setting and the noise increased and stayed solid. When I got home, I pulled the fuse on the PASM and checked for the AM radio noise in the "IGNITION ON" switch position. Noise gone. Now I know that the noise is probably the PASM pump. The questions are why and how, and how do I stop it. It seems like Porsche should have designed noise suppression into the system. Any ideas?

[mudman2]

Thats Porsches problem, its a wiring issue. I did some tests and I hear no noise from the pumps.

Edited February 6, 2005 by mudman2