Garmin losing signal

[bc-short]

My apologies if this has been answered before. I did look for my problem but haven't found anything.
Problem: I just bought a new Garmin 2555 (replacing a 350 that worked fine). I have it mounted on a Pro-Clip just to the right of the clock. This is the same place the 350 was mounted. The new GPS is unable to maintain signal. At one point it reported we were traveling at 579 mph - that's pretty good for a 08 Highlander. If I set the unit on the dash it works flawlessly. There seems to be a "dead area" within 6 inches of the center dash console. Turning off the CD/radio has no effect.

I have read about windshield coatings that can interfere with GPS and radar detector signals. This doesn't seem to be the problem. I am thinking that just maybe it is some electrical interference that is causing the signal loss. Possibly the bluetooth or the keyless entry.

Is there a way to disable the Highlander's bluetooth - without dismantling it? Does anyone have any other ideas? I would really like to keep the GPS mounted up by the clock/rear view display screen if at all possible.

[TrailDust]

Here's a past thread discussing this same issue. I'm not saying you didn't find it in your searching or that it has an answer to your issue, but rather I'm just throwing it out there because of its relevance.

I'm wondering if the issue may be with the Highlander's windshield. GPS signals are by nature relatively weak, and they're already susceptible to refraction in the upper atmosphere, as well as local refraction induced by local structures that "tweak" the signal on its way to your antenna. Also, there are definitely differences in the antennas each company uses for their GPS devices, and even differences within a company's product line. My Magellan GPS works perfectly fine when I have it sitting in my center console cup holder, yet a Magellan I owned before that one functioned intermittently when even holding it on the dashboard, and yet when I stepped outside if functioned perfectly fine. I'm wondering if this is a GPS antenna issue.

[PhotonDreams]

I have the Garmin 1490 and it's been mounted directly in front of that basic clock and have had no problems with it picking up a full bar of satellite signals. So, I'd guess that the windshield in not a problem. You might update the software online since I've found that it tends to solve problems with a Garmin from time to time. Other than that I'd suspect the unit, though you might want to take it to a few other cars and test it there.

[bc-short]

Thanks for the information. I am aware of the problem with athermic windshields and am pretty sure this is not the problem. I am leaning toward electronic interference because of the following:
1. My previous GPS was a Garmin 350. It had some trouble acquiring satellites if I started the Highlander before the GPS. Once it got the satellites it held them with no problems. The 350 has a swing out patch antenna that has a pretty fair amount of surface area. The 2555 has an internal antenna that I assume is much smaller and is not oriented toward the sky. I have tried two 2555s and both have behaved the same. They are unable to maintain a "lock" on the satellites when mounted in front of the center electronics console (my word for it. I'm not sure what you call that grouping of CD/radio, back up camera display, clock, A/C controls, etc.).
2. I can move the GPS to the side or above the console and as long as it is more than about 6 inches away from the outside edge of the console, all is well. I can put the GPS anywhere on the dash and it works well. There just seems to be a "dead zone" centered around the console.

My Highlander is a '08 Limited without Navi (obviously). I have updated the 2555's software - it's new but I updated anyway.

Any ideas or suggestions are welcome. Thanks.

[05Moose]

Okay, I'll throw this question out there. If you find the source of the interference (let's assume it's the radio for a moment), what will that solve? You'll still have a dead zone. I just had to ask that question because I don't know that finding the source will be of help to you unless you plan to replace the garmin. And you said it's not the radio because you turned that off. I think about all the warnings with home electronics saying not to place one above or next to another one etc. The radio still has power even with the button turned off. Why not pull fuses for the various electronics to truly disable them as a process of elimination?

[bc-short]

Thanks for the input 05Moose. That's a really good question. What I was hoping to gain from this discussion was some insight from someone that really knows the electronics of my Highlander and might have some ideas about how to deal with it.
If it is the bluetooth that is causing the problem, I could potentially disconnect it and problem solved (I don't use it anyway)! If it's the keyless entry/ignition, then I'm stuck.
I think your suggestion about pulling fuses one at a time is a good one and I will try that when I get home (we are on a road trip right now).
If the interference is not readily fixable then I can live with it. We purchased a rubber mat kind of a mount that sits on the dash. It's working fine, it's just not as elegant of a solution as what I had before.
Just as a note of interest, the GPS is sitting on top of the center of the dash, right near the edge about 4 inches from the old position. Go figure!
Again, thank you for your input.

[nov0798]

Ive been experiencing a similar issue with a Tom Tom. If I place it above the clock in the center of the dash, it never acquires a signal, however if I place it on the drivers side just in front of the speaker, the signal acquires. Really strange. My wifes Rav4 doesnt have this issue. Again really strange!