I had mine go dead a few times and fail to power up or start the car. I got warning messages that had to be reset the same way the maintenance required messages are dismissed.

When the car was new, the battery discharged in 1-2 days when I left my GPS plugged into the cigarette lighter. A few years later, leaving the GPS mount/traffic radio plugged in sans GPS discharged the battery in 1-2 weeks. A few days with it plugged in would lower the battery voltage to 11V. Unplugged, it would be 12.2V for two weeks. My multimeter detects no voltage in the cigarette lighter socket when the car is off but leaving the GPS mount plugged in consistently leaves me with a dead battery if I don't drive every few days.

I used a car battery float charger to charge the battery the first few times and then my fancy RC battery charger recently.

 

What kind of battery charger do you have? THis works on the AGM battery without causing damage??
Thanks

 

Back in 2007 I used a cheap float charger from the Sears auto dept. The RC charger is an iCharger 206B which, like many RC chargers, can charge almost any type of rechargeable battery out there. Just set the battery type (lead acid), cells/voltage, and charge rate (~4 amps) and let it do its thing. It even generated a nice charge graph for me to view on my PC.

 

To charge these AGM batteries, it is important to use a charger that has an "AGM" setting. AGM batteries can be damaged by too-high charging voltage. Standard lead-acid chargers us higher voltages to achieve constant current. The "AGM" setting limits the voltage.

 

Great Thanks!!!

 

Just an fyi -- Information about how to charge Optima-brand AGM batteries is on the manufacturers web site at:
http://www.optimabatteries.com/produ...t/charging.php
I am sure that much of that information also applies to other brands of AGM batteries, due to the nature of batteries having similar chemistry and construction.

 

So, I assume the Toyota brand is Optima. When I went to the dealer they just said you had to get a new battery through them.

Thanks

 

Quick question anyone:

If the pole is removed from the 12V when putting the car in storage, will there be damage to the hybrid battery in the front of the TCH?

Doesn't the engine need to be run as well or is it just the 12V that needs to be charged?

I was told to take the pole out of the 12V as I will have to leave the car parked for more than a few weeks but I just want to make sure the engine will be okay and the hybrid battery.

 

No. Information about the Toyota 12-volt battery is hard to find. It is an AGM battery, but I don't know who actually makes it. Toyota uses a lot of Denso electrical parts. They might even have multiple sources.

Optima is a separate company that also makes AGM batteries. Some people have used Optima batteries as replacements.

Optima recommends certain charging procedures. I would expect that the charging procedures for the OEM battery would be similar.

The OEM battery does have a temperature sensor. Most others do not. Another thread on this site suggested that the temperature sensor can be transferred from the old battery to the new.

 

I did not know that there was any pole in the 12V battery that could be removed.

It might be good to disconnect the battery, or to use a trickle charger.