NUVI 660 Battery Life

The most I ever got out of mine in the car just using the map was 3½ hours when the "Low Battery " displayed, but I run mine on AC so no problem there. They don't last as long as the 550C.

Bluetooth, WAAS, screen brightness, MP3 player ... all of these will use battery life. 3 hours sounds about right.

I forgot to take my GTM20 adapter on my last trip to Boston and got an average of 2-1/2 hours between the charges (I recharged it via my laptop). This is based on brightness at 100%, Bluetooth, no MP3 playing, & half of of the time using the routing engine (with TTS enabled).

When I go on a trip and use my GPSr on battery power, I make sure to turn WAAS off (Normal). This conserves significantly on battery life. At night I charge through my PC's USB connector.

I never enable WAAS. I don't even know why Garmin left it in the 6xx units in the first place as it's an obsolete technology compared to the SiRF Star III chipset.

I guess it's a marketing thing (another 'feature' to list)

Using just the GPS function, I get almost 3 hours of battery life from my 660. I found this out while flying from the East to the West coast.

It is still in development as primarily an aviation nav-aid, and Garmin, being big into aviation equipment too, is working it into their consumer models because the technology add more precision to the GPS signals.

You're correct Keith, I should have qualified my statement for driving. I have several friends working for Honeywell for aviation safety. WAAS was created for the aviation industry and was mostly intended to enable instrument approaches to airports to be safer. But that increased safety is brought about by the improvement in altitude reporting with WAAS on, not the horizontal accuracy. For street routing, the altitude doesn’t matter, but the altitude is critical to an aircraft trying to land.

With WAAS, your horizontal accuracy goes from 10M (approx 33ft) to 3M (10 ft) in best case. I doubt people driving can even tell the difference or care. For street driving, SiRF beats hands down because it has greater signal sensitivity and SiRF protocols provide more complete control of the GPS receiver as well as higher speed communications between your GPS receiver and the mapping/display engine...which gives more accuracy (well, at least perceived). This is probably why Garmin send their unit out with default WAAS setting to 'disabled'.

When the USB charger is plugged into the computer, you can't use the unit correct?

I went in to eat lunch and plugged the unit into the usb cable and the cable to a portable battery charger. It said connected to the computer. When I unplugged it the screen stayed on as connected to the computer. I had to reset the unit to get it to work.

That 'altitude' thing can matter on stacked roads - that's where WAAS can come into play - they're working on using WAAS enhanced coordinate fixes to see what level on a stacked highway you might be on, and provide appropriate guidance.

I'm not sure what you mean by portable battery charger.
When I connect my 660 to the AC adapter that came with it, I can still use the map.

When I connect it to my laptop, the laptop recognizes both the Nuvi built-in and SD card as external storages (and see the 'connected to the computer' picture). You'll have to remove these drives first using the 'Safely remove hardware' feature before disconnecting your Nuvi. Otherwise, you Nuvi will stay in that mode (it's a bug in their USB support). You can either reset the device as you did or re-connect the USB cable and then perform the above mentioned step to properly disconnect.

Hope this helps.

we usually get about 3 hours on our Nuvi 660 and on long trips we use the travel charger.