Garmin 430W won't acquire satellites

thompsonbr87 · #1 07-15-2019, 08:51 PM

I'm finishing up installation of a Garmin 430W and it is not acquiring satellites. After about 10 minutes, I get, "GPS is not responding. Check GPS antenna." I've tried the 430w in another airplane, and it worked fine. Antenna cable has no shorts from signal to ground. Antenna is a new GA-35. Cable is about 17' right now (planning to cut it down later). The satellite status page didn't appear to acquire anything, so maybe a center pin is not making good contact? Any way to test this? Other ideas? Thanks in advance!

BobTurner · #2 07-15-2019, 10:19 PM

Pull off both connectors, make sure the center pins are locked in position.
Use your ohmmeter to make sure pin to pin has continuity (may need some wire and/or an assistant). Do the same for the shield connections.

mturnerb · #3 07-16-2019, 12:30 AM

Same tray as other airplane? In addition to checking antenna and cable continuity, make sure tray is right and antenna connection is seating properly (and that radio is seating fully in the tray).

noelf · #4 07-16-2019, 04:10 AM

Check to make sure the GPS antenna / coax cable actually go to the GPS input on the 430 back plate.

9GT · #5 07-16-2019, 06:38 AM

Make sure the plane is outside of the hanger with good access to the sky also. My GTN650 could not acquire a satellite signal in the hanger but my G3X could!

thompsonbr87 · #6 07-16-2019, 07:44 AM

Continuity between the pins is good. Same for the shields. I connected a different antenna/cable combination into the backplate, and the 430 began picking up satellites slowly (which I understand is typical for a unit that has not been used recently), but eventually picked up more satellites than I cared to count. Visually inspecting the cables, I'm now suspecting that one (if not both) of the pins may not be protruding far enough. I supposed the antenna (brand new from Garmin) could be bad, but the chances that my first BNC & TNC connectors are flawed seems much more likely.

bkervaski · #7 07-16-2019, 07:48 AM

Did you check for continuity between the shield and the pin? There should be none ...

thompsonbr87 · #8 07-16-2019, 07:52 AM

Quote:

Originally Posted by bkervaski

Did you check for continuity between the shield and the pin? There should be none ...

Yep. That was suspect #1.

airguy · #9 07-16-2019, 08:54 AM

What do you have operating that could be creating interference near the antenna? Some other GPS antennae have been demonstrated to give Garmin's antenna problems when in close proximity, I know Dynon GPS 250/2020 do not cause that problem but have not tested any others.

You could remove your current antenna and simply place it anywhere else to determine if you've got interference.

BobTurner · #10 07-16-2019, 11:52 AM

Quote:

Originally Posted by thompsonbr87

but the chances that my first BNC & TNC connectors are flawed seems much more likely.

I did the same thing on my first TNC install. There should be a definite "click" as the center pin locks into place. Otherwise, the pin gets pushed in when you attach the connector. If you can push the pin in at all, it's not right.