Trouble With nuvi 3790T


I recently purchased a Garmin nuvi 3790T
Software Version 2.50
GPS Firmware 2.20
I have downloaded and installed (through the POI loader) “Rest Areas Combined”, along with “Red Light and Speed Cameras”. Under “Proximity Points” it shows “Custom POIs” with a checkmark and “Alerts” Enabled.
Rest Areas Combined
Travelling South on Interstate 35 from Minneapolis, MN, through Iowa and Missouri and having passed numerous Rest Areas my unit does not alert me to the proximity of them. I can view the “Rest Areas” if I go to “Favorites” ”Extras” ”Custom POIs” I find the “RestAreasCombined(Ver.Z)” there (along with the “Redlight-Cameras” and “Speed-Cameras” .
My question here is, Should the unit not alert me to the proximity of the Rest Areas, or, do I have to go to “Extras” and select each individual Rest Area I want to go to each time?
Red light Alerts
Red Light (Safety Cameras) work. But, a small window (very difficult to read when driving) pops up and alerts me with a ‘pinging’ sound. Along with loading the custom POI Red Light Alerts I have loaded a MP3 voice alert (renaming the MP3 EXACTLY the same name as the Red Light file except for the file extension. The MP3 voice alert does not work.
I had a Garmin c330 unit and it did a better job of alerting me of the Red Light alerts and Speed Cameras.

Voice Command
Sometimes the “Voice Command” works good. But I noticed that I have to turn off the radio and the A/C fan to get a quiet atmosphere. They seem to interfere with my speaking to the unit. I also notice that in the quiet mode I sometimes have to yell at the unit before it responds. (Makes people outside the car think I’m nuts).
For the price I paid for this unit I’m not too happy at this point.
Any suggestion would be greatly appreciated.
Yours truly,


You need

You need to use .wav files for voice alerts as, like many newer Nuvi models, the 3790T doesn't support MP3. There are lots of free programs that will convert your existing MP3 files to wav.

The ability to use voice commands will always depend on the noise level in your vehicle. Many members have posted that they need to turn the radio down for this feature to work properly.

Nuvi 350, 760, 1695LM, 3790LMT, 2460LMT, 3597LMTHD, DriveLuxe 50LMTHD, DriveSmart 61, Garmin Drive 52, Garmin Backup Camera 40 and TomTom XXL540s.

Check out the FAQs

1- when running POI Loader to install Rest Areas Combined, are you running it in manual mode and setting an alert distance? Running POI Loader in Express Mode--or in Manual Mode without setting a distance--will not give you alerts. Pertsonally, I use 15000 feet for my custom alert distance for rest areas.

2- From what I see, the 3790T doesn't play mp3 files. You will need to check the FAQ regarding using wav files with SOX.exe to get custom alerts. Yes, the popup windows are pretty small.

3- my 855 also has issues with voice recognition at times. If the 3790T can accept a plug-in microphone, you may get a better response with it. A radio is not much different than having talking passengers and they will confuse any voice recog. system.


No way to plug a microphone into a 3790.

Nuvi 350, 760, 1695LM, 3790LMT, 2460LMT, 3597LMTHD, DriveLuxe 50LMTHD, DriveSmart 61, Garmin Drive 52, Garmin Backup Camera 40 and TomTom XXL540s.


Thank you very much for you help.