Hi folks,

I left my Camry sitting in my garage for a couple of days unused, as I tend to use my 4 wheel drive when there is too much snow on the ground. To the best of my knowledge nothing was left on, however it seems the electrical system is nearly or completely dead.

Ex.
-Door locks/lights do not respond to FOB.
-I get a very dim overhead light in the cabin when I get into the car.
-When attempting to start, there is no response at all, aside from the status light on the power button changing from orange to green. Nothing from the dash -at all-. No clock display. No radio, etc.

What are the functions of the 12v vs the "hybrid" battery? Are they both dead? WHY? I have yet to try to jump it, but I will and will report back.

 

There are some posts regarding the functions of the hybrid battery and the 12V battery. I thought the hybrid battery was actually used to start the car and the 12V was to keep the computer, clock etc. active. I have left my TCH sitting for 2 weeks and never had a problem. Did you do a search? Good luck, let us know what you find out please.

 

kids... grr

 

Your little 12v battery is discharged, but the Traction battery is probably fine as it is disconnected when your TCH is off. When you jump your TCH, be very careful to get the polarity correct as reversing the polarity can do serious damage to the inverter ($$$).

The 12v battery is there to run some pumps and boot the computers or run the accessories in "ACC" mode (take care not to run down the 12v battery). Keep an eye on the health of the 12v battery as running it down (as you just did) does weaken its capacity to hold a charge.

Once your TCH is in "READY" mode, the Traction Battery takes over and the "INVERTER" (actually its DC-DC converter) generates about 14 volts to run all of the accessories and slowly recharge the little 12v battery.

JeffD

 

I had a nail in one of my tires and took my 2007 TCH into a local tire center to have it repaired. When I went to pick it up the next morning, the car would not start - the battery (12v) was totally dead (the interior lights would not even go on at all). After having it jump started, I took it over to my local Toyota dealer who informed me that the 12v battery needed to be replaced. It may just be time for a new battery. What year is your car?

 

The 12V battery in your 2009 TCH should be OK after a good recharge. After recharging, measure the voltage at the battery with no load after sitting for a few hours. Look at the attachment for what voltage is acceptable at a given temperature. This chart is for AGM batteries.

 

The battery may have deteriorated if it was left in a discharged state for too long. It may still work after being recharged but with diminished capacity.

 

There are some products out there that 'claim' to reverse the effects of sulfation. Has anyone tried one?

 

Not since I was a teen... Never saw any "improvement" until I replaced the battery. Push starting an old Nash Rambler is not much fun.

In my humble opinion, it is not worth the aggravation and time to mess around with a marginal battery. If a battery gives me any cause to question it's performance, I replace it.

jayw_TCH - I would replace the battery as it was all but dead after a few days. If you do jump it, I suggest putting a 2 amp charger on the battery overnight to bring it up. The TCH Owners Manual cautions against using a battery charger of over 5Amps (page 397). After charging or driving the TCH, wait at least 2 hours, then measure the battery voltage. If it is under 12.4Volts, I suggest getting a new battery. If it is under 11.8Volts, you have a bad cell in the battery.

 

Make sure your clock is black (not lit) when you leave the car. If the clock remains lit, it means your ignition is on and will pull down the battery maybe overnight. Press the PWR button till the clock is off.

All the car batteries I have seen, if drained down to 10% to 15% they will not hold a full charge and will pull on the alternator or generator.