Auto shut down

Yes, I have heard of this. I also read (on a different forum) that the nuvi thermal protection will shut off the charging power within a certain temperature threshold to prevent the heat caused by charging. The unit will continue to operate from battery, but will not charge. So eventually your battery drains and shuts down even though you are operating with the power cord plugged in.

Sorry, but I can't verify that a thermal shut-down exist by researching the net and Garmin.com. Searching my manual (that covers the 1200/1300/1400 series) I found nothing to support this idea either.

My model is a 1200 and I would expect that some mention would be made about keeping the unit cool, and there is: 0 to 140 degrees F is the operating range.

The charger has a fuse, not a thermal cut-off circuit.

So my conclusion is: Your model may have a thermal cut-off but my unit does not.

Being in Arizona this could be fun. This is our first summer with GPS's

But I don't keep it in the car in plain site.

Another reason not to leave it in your vehicle. The main reason - THEFT.
I always disconnect it and take it with me. Also, I use a vent mount - keeps it out of the window and the a/c keeps it cool.

I know garmin dont mention it in my manual either,(which they are the same manual) after it happened i looked for that,this the only time i ever heard of it at all. I would suspect if you did leave it up in the windshield for a while it would happen, i think this is just one of the features that Garmin dont talk about.Why? i dont know. I just figured i would thow it out to the community and let them know that if it does happen to them what to expect.

I wasnt worried about anyone stealing it when i left it in the windshield, Where i was there was a LEO right there and a lot of people coming and going. so that wasnt a consern. BUT now at least i will put it on the floor away from that blazing heat,

I would be more careful even with LEO or people around. My friend's gps was stolen from parking with security guards and CCTV. And of course it was never seen after it and nobody was apprehended. Police doesn't even bother to look for it, they just make "report". And that was it. He had to buy new unit.

It took some research, but I finally found the post in the GPSReview forum that addressed this. It points to an Amazon user review which references the nuvi 1350 User Manual. In the Troubleshooting Appendix:
Problem: My nuvi does not charge in my vehicle.
Solution: Your nuvi can only charge between 32 F and 113 F (0 C and 45 C). If the nuvi is placed in direct sunlight or a hot environment, it cannot charge.

I can believe all of the units would have a thermal shut off.

Why? They all have a processor, and the CPU has an operating range to it to avoid damaging the CPU, as well as the motherboard. Virtually all of them have a built in sensor.

From Garmin:

Question : How does temperature affect the power and charge of my device?

Answer:

All of our units that have a rechargeable battery contain something inside the battery called a thermistor. If the thermistor inside the battery registers a temperature at or below 0°C or at or above 45°C1 (32 °F and 113 °F respectively)1 the charging mechanism within the unit will shut off. When the unit is operating outside of this temperature range the unit will operate solely off of the external power source and will not charge the battery.

When the unit is within the 32 °F and 113 °F temperature range, the external power source will power the unit and charge the battery. The unit's charger will always provide 100% to the unit and send any extra power to charge the battery.

As a preventative measure do not leave your device in direct sunlight. By keeping the device out of direct sunlight the unit is more likely to charge when getting into a hot vehicle.

The best thing to do if your device is not powering on in the vehicle, or your battery is only lasting 30 minutes is to charge the unit overnight by using either an AC adapter or USB Cable attached to a computer. Charging from a USB cable connected to a computer will charge the unit at 30-50% of the rate of which it would charge if plugged into a 12-volt vehicle power cable.

1. Temperatures within the vehicle generally tend to be warmer than the temperature outside of the vehicle.

113 degrees F (45 C) is not hot at all. I'm surprised that low value is [supposedly] used. I leave my Nuvi in the car all the time, and summers in Dallas often get over 100F. A car setting in the direct sun will definitely get well over 113F. I have not experienced any problems. Something doesn't sound right...

I was not aware of this. I live in Texas where it get very hot. I normally remove my GPS from the dash when I leave my car to help reduce chances of theft anyway.

I agree with Koot. I have never had any issues with my units on hot days in DC.

Koot - It was 110 degrees F in Montgomery, Alabama yesterday afternoon, with 90% humidity. It was hot! 100 degrees plus is hot. I don't care where you are.

I think Koot was commenting that it is not unusual to get up to 113 inside the car ... even with cooler outside tempuratures on a sunny day, it easily gets up to 113 inside the car.

Why leave electronics on a hot dash in the sun? It can't do any good for them.

Also, I use window shade covers, especially the flexible ones that you can pop open, to shade the dashboard / car.

Every little thing you can do to keep the car cool will benefit you and the car.

I agree!

Page 53 of the the Nuvi 1200/1300/1400 series manual:

Operating temperature range:
32 F - 140 F (0 C - 60 C)

Charging temperature range:
32 F - 113 F (0 C - 45 C)

Just because there is a microprocessor in the GPS, doesn't preclude that the manufacturer is required to protect it from heat, abuse or mishap. That's the reason they provide a set of operating specifications. If you ignore the specifications, they are not responsible for damages that may occur.