Well I installed my AVIC-F900BT last summer (early adopter) myself. I did a textbook installation and everything went perfect. I ran the GPS antenna wire down the side of my car and up to the roof. I placed it on the edge of the roof in the back corner. I noticed lately that I am getting really poor GPS signals. Most of the time I can only acquire 9 satellites and none are green. Most are yellow and a couple of reds.

Today I took the interior out of my car for a deep cleaning and I decided that I wanted to do something about my satellite signal. I pulled the antenna off the roof and pulled up all of the cord to decide on a new place to put it. Just out of curiosity I put the GPS antenna on my other car (parked right next to it) to see if I get any signal improvement. ABSOLUTELY NOTHING! I saw no improvement in signal and it's driving me crazy. (both cars were parked outside next to absolutely no trees, nothing but clear open sky)

Should I be getting any green bars? Is my signal quality actually low or am I just nuts? I feel after all of the work of running the antenna wire and finding the perfect placement, I should have at least one green bar.

Also, I have a second GPS antenna for this unit. Has anybody ever done a dual GPS antenna setup? Is this even possible? Will it confuse the F900BT?

Thanks in advance!

Honestly, my best luck with gps signal has been on the front dash dead center up against the window glass.

Your mileage may vary. But that's where mine sits. Glass is a lot more radio transparent than metal.

What kind of signal quality do you get? Do you get some green bars?

I was considering placing the antenna under the dash right near the windshield but I can't access that area. I can't really get under the dash near the windshield so I couldn't even really place the antenna on top of the dash at the front near the windshield. I do want a more factory look, it would be awesome if I could find somewhere to hide the antenna where I can't see it and get a great signal.

I think I may also call Pioneer tomorrow and see what they say. It's pretty ridiculous that I don't get green bars with the antenna outside the car.

You probably tried.... did you just try using a different antenna? Or are both antennas giving you the same issue?

I did plug in the second antenna and I got the same exact problem. That's when I got the idea for the dual GPS antenna setup, which probably won't work because the antennas are probably amplified (or maybe not, which could explain my problem?).

You said that "lately" you've been having problems, which implies that you weren't before. If that's the case, and you did already try swapping antennas, I'd suspect that something has gone wrong in the HU itself. Multiple antennas may introduce their own problem, something called multipath propagation:

http://en.wikipedia.org/wiki/Multipath_propagation

Think of it as causing your receiver to hear echos of the radio signals, which it then has to try to interpret.

Well I called Pioneer and they told me to send it in to be checked out. Before removing the unit from my car I decided to upgrade to the 2.006 software. I now get mostly green bars (well, yellow/green) on the satellite signal page. Although the bars are green, they do not fill up the little progress bars for each satellite (only about 70%). Will the little progress bars fill to 100% to indicate the best possible signal? Does anybody actually have any of their progress bars 100% full?

Well I called Pioneer and they told me to send it in to be checked out. Before removing the unit from my car I decided to upgrade to the 2.006 software. I now get mostly green bars (well, yellow/green) on the satellite signal page. Although the bars are green, they do not fill up the little progress bars for each satellite (only about 70%). Will the little progress bars fill to 100% to indicate the best possible signal? Does anybody actually have any of their progress bars 100% full?

Bars usually indicate signal to noise ration of the signal, not strength per se. I have never seen all bars full on any GPS receiver, but as long as you get 4 bars in green, you are getting enough data for accurate 3D positioning.

Bars usually indicate signal to noise ration of the signal, not strength per se. I have never seen all bars full on any GPS receiver, but as long as you get 4 bars in green, you are getting enough data for accurate 3D positioning.

Getting all satellites to have a perfect SNR would indicate a serious software problem. Even is you assume that all sats are exactly similar in build (antenna, radiated power etc.) and the field of view of your antenna is completely free, which they both are not, they are on different distances to the receiver and since SNR decreases with increasing distance between transmitter and receiver, you should see differances. If you take some time to observe these signal indicators, you should see different sats coming into view, with signal strength increasing as the distance between you and the sat decreases, followed by a decreasing SNR when to point of closest approach is passed. A very nice graphical representation of what is happening can be found here : http://www.gano.name/shawn/JSatTrak/

Getting all satellites to have a perfect SNR would indicate a serious software problem....

Or hardware...