BU-353 Low Signal when starting in underground garage

**fatejd** · 06-02-2010, 01:38 PM

I have my system running CF3.1 with GMPC (it did the same with Destinator) and park in an underground garage (work or home), where it hibernates. When I resume, most of the time it either never gets enough satellites and locks or it takes a long time (at least 10 minutes), even if I get out of the garage before it finishes resuming. I'm guessing this issue has to do more with the state of the GPS when I hibernate the PC after entering the garage. It seems like this could be fixed possibly by a disable/enable of the GPS driver just like Xport does when it resumes. I have Xport running and this still occurs and the Xport GUI reports "Low signal". I have a GPS log from this morning when this occurred and can post it, but it doesn't look very helpful.

Anybody have the same problem? Ideas?

**Nomader** · 06-02-2010, 01:51 PM

the unit has an internal capacitor (battery) which keeps the sat info in memory... if you leave it for long..the capacitor will discharge and you will lose the info, thus the unit will have to re aquire it.. it can take up to 5 minutes or even more and of course it needs an open sky above to see the sats..

**fatejd** · 06-02-2010, 01:57 PM

Originally Posted by Nomader

the unit has an internal capacitor (battery) which keeps the sat info in memory... if you leave it for long..the capacitor will discharge and you will lose the info, thus the unit will have to re aquire it.. it can take up to 5 minutes or even more and of course it needs an open sky above to see the sats..

I don't have the same problems when I park outside...

**Punky** · 06-02-2010, 02:00 PM

its just what happens when you complete loose all your satellite signal, it'll have to go through a cold startup, and it takes hella long. Unfortunately its a limitation of the gps, and there's not much we can do.

**fatejd** · 06-02-2010, 02:02 PM

Originally Posted by Punky

its just what happens when you complete loose all your satellite signal, it'll have to go through a cold startup, and it takes hella long. Unfortunately its a limitation of the gps, and there's not much we can do.

That's kinda what I was thinking was the problem. I just wonder if there is a way to reboot it or something once I am under a clear sky...

**RipplingHurst** · 06-02-2010, 02:11 PM

I had this problem with my Garmin GPS 18 usb. It would lose signal completely in my garage (mounted inside the car). It would like 15min to reaquire signal, which was completely inacceptable (If I just parked outside with the carputer on, it would take 8-10 min, so moving, specially moving fast down the highway, made it to take longer to get usable signal).

I then mounted outside the car, it takes about 5min, which is supposed to be normal. Same GPS, carputer, driver, everything, just mounted outside. It acquires much faster.

**yonu** · 06-03-2010, 08:10 PM

If I may make a suggestion which has worked for me. Get a LM7805 and wire it to only the power lines of the GPS and provide it power from a constant 12v source even when the pc is hibernated this should keep the GPS running and keep a lock.

Hope this helps,
yonu

**Punky** · 06-03-2010, 10:42 PM

Originally Posted by yonu

If I may make a suggestion which has worked for me. Get a LM7805 and wire it to only the power lines of the GPS and provide it power from a constant 12v source even when the pc is hibernated this should keep the GPS running and keep a lock.

Hope this helps,
yonu

this works great if you're not underground. If you're underground (parking) for a long time, it will loose the lock anyway, and wait a while you'll still back to the same problem.

**yonu** · 06-03-2010, 10:46 PM

ok figured it was worth a shot. I don't have to worry about underground parking here. So wasn't sure if it could keep a lock if left on or not

**scENFORCER** · 12-05-2010, 11:59 PM

I was having this same problem. I figured out that if you go into the CF's Advanced Setting/Navigation, dont change anything, and simply then exit out of the settings (it will ask you to save the changes which of course you didnt make any, click Yes), the GPS then locks on immediately.
Its kind of a round-about way of doing it, but its better then waiting the 10-15 minutes before it reacquires the signal.