New batteries; worked great for two days; now will not turn on, either unit!

Hello Kathy, The first thing that I would do is change the batteries in the thermostat. One or more may be weak and not turn on your furnace. I would put in Alkaline batteries. If that doesn't help, maybe a new thermostat is in order.

Check if the unit has a breaker on the back and reset it. The unit doesn't seem to be getting power.

Go to the head unit and then to setting.. In "General" select the option "Auto Off" and switch it to On.. It make you sure that no matter if the radio stay on, after switch off the ignition, it will turn off automactly after a few seg without the use!

your charging system isn't working, if you replaced the battery and it worked for a few days, then its not being re charged after starting, I'm assuming you cleaned and tightened all the battery post connections when you installed the new battery , if not do so ,, charge the battery from an outside source, once you know its fully charged,, use a meter, and start the car ,, check the voltages at the battery posts,, you should be getting a reading of 13.5-14.5 volts, if not your alternator isn't charging the battery

Check power supply to the unit with a 50W 12V bulb as load,voltage should be at least 12V,with batteries full charged

• Try to charge the unit for 8 hrs using the wall adapter and then try to power on the unit, if its still the same and it will not power on try to call for the tech support so that they can replace the unit if they can't fix it and don't forget to have the receipt number for reference.
  

I’m happy to assist further over the phone at https://www.6ya.com/expert/ramy_d9e7ebea3891f482

Did you use rechargeable batteries? The Garmin seems to be extremely picky about enough voltage. I had good rechargeables which I use in my foto flashlights, but they did not suffice for the Gamin. Simple non-rechargeable batteries ones solved my problem. Not good for the environment, but for my bearings...

most likly where the battery is suppost to touch on the inside of the radio, it is not touching all the point on the radio.

Ok, try this. Remove the batteries from the keyboard, just type anything randomly for about a minute on the k/b keys (doesnt have to make sense) Just press as many keys as you can. This will discharge the capacitors and reset the k/b. Reinsert the batteries, making sure they are in the correct alignment (try to use new batteries if you can) and connect to reciever. Press the connect button on receiver first, and then press the connect button under the keyboard.

If that still doesn't work, then your keyboard is most likely defective. Make sure you have reinstalled the k/b software first from Logitech..

When I bought my Imate I had the same problem. Put the charger on it and leave it for an hour or so and check the results. Just so the backup battery gains charge.