[junkone]

I got my sienna CE in 2005 and in 2010, i had left my car without using it for 1 week. When i returned, it never started. Jump starting did not help as the battery was not holding charge. I replaced it with a energizer battery in Walmart
last week, 2013, i had left it when i went away for 1 week and same story. this time the energizer battery lasted 2.5 years until i replaced it in Walmart.

how do i predict these battery failures so i can get it replaced before the failure.

 

[fibber2]

5 years on an OEM battery is actually pretty good. These units are usually rated for 36 - 48 months, so you did fine. Our '08's battery began giving us problems in 2012.

2.5 years on your replacement is short, so the question is why. There are things on modern cars that draw current all the time when the ignition is off, so the load isn't zero. Still, a good battery should last a month or more, and once jumped should come back to life just fine - unless it froze. The variable here is the battery chemistry. When a conventional lead-acid battery is fully charged, the electrolyte is a strong acid which has a very low freezing point. When a battery becomes depleted, the specific gravity of the fluid approaches 1.00, or close to plain water. If it freezes, the expansion bends and can short the plates, and its permanently damaged.

The other possibility is that it's just a defective battery and died early. Some do. See if it happens again after the van sits for a week. If so, blame the van's electrical system and start hunting for what is drawing too much current.

 

[disconnect]

Have had identical ongoing problems with Toyota Siennas. Bought new 2006 Sienna AWD. loaded. Battery dead most of the time when it was left unused for 1-2 weeks..(specially at the airport at 1:00am). Toyota dealer could not find any problem. Dealer suggested we buy new battery which we did, from Toyota, but problem has remained to this date. Also purchased two new 2011 Siennas (loaded)...Same problem.....New dealer says everything checks out but was unable to solve the problem. Same conclusion...need new battery. That was 2 years ago, still using old battery, but purchased a portable rechargeable battery $75.00which we carry in each vehicle so we can start it anywhere, anytime. A lot of effort, and time consuming. You may wonder why we go to all this trouble to have Toyota Siennas'. We have found the AWD works better than any other vehicle we have owned, and that is why we keep buying them. But...we feel that having to open the door with a key, lift the hood, connect the charger and start the vehicle, is becoming a pain.
I found out today that you can purchase a battery dis-connect switch from NAPA (for another $75.00), which can be mounted on the battery. This means all I would need to do is open the hood, lock the van, turn off the switch, and close the hood.
Is this the only way one can continue to own, and operate Toyotas' top of the line van?

 

[jc]

How fancy is this battery switch? I have a cheaper solution, 10 mm wrench and remove the negative battery terminal. Sounds like you need to disconnect the battery if your not using it for a week.

Regards, JC.

 

[disconnect]

How fancy is this battery switch? I have a cheaper solution, 10 mm wrench and remove the negative battery terminal. Sounds like you need to disconnect the battery if your not using it for a week.

Regards, JC.

Yes, that is a great solution, and it would work fine...Since this often happens late at night, with the temp at -30, with my luck, I would drop the wrench under the vehicle....Surely Toyota could come up with a factory fix with the same idea installed under the dash.

 

[fibber2]

You can buy those battery disconnects even at Walmart for a few $$$ - they have a green plastic knob on the top to switch on and off. BUT - they create a major issue on modern cars! Zero power wipes out the ECU learning along with radio presets, etc. This can create hard starts, poor idle (see the Throttle Body TSB), and even make it impossible to pass a state inspection (readiness indicators). There is a leakage path somewhere, and an experienced electrical tech needs to hunt it down.

 

[jc]

What about something like this with a cutoff and bypass?

http://www.princessauto.com/pal/Battery-Accessories/Top-Post-Battery-Master-Cut-Off-Switch/4210962.p

Regards, JC.

 

[fibber2]

Unless that fuse is limited to 350 milliamps or so, he'll still come back to a dead battery after 1-2 weeks. You need to find the cause.

 

[disconnect]

Thanks for the input. I agree that I need to find the cause...I have tried to talk to Toyota who has been unable to find the reason on all three of my Siennas...I feel it is a manufacturing defect but they deny that there is anyone else having this problem...

You are right, what you are saying about shutting off all the electronics would just be a bigger pain. (Cheaper switch may have lessor current carrying ability). I may try to just bring 2 cables out through the grill to hook up my trusty portable battery (which doesn't go dead in two weeks) ..Or if Sienna is so dead I can't get into the vehicle even with a key, I can call roadside assistance to give me a boost.

 

[ranwan78]

I got my sienna CE in 2005 and in 2010, i had left my car without using it for 1 week. When i returned, it never started. Jump starting did not help as the battery was not holding charge. I replaced it with a energizer battery in Walmart
last week, 2013, i had left it when i went away for 1 week and same story. this time the energizer battery lasted 2.5 years until i replaced it in Walmart.

how do i predict these battery failures so i can get it replaced before the failure.

Toyota has what they call a "short pin" in the fuse box in the engine compartment. Its used to keep the battery from going dead in shipping. It looks just like a fuse but a bit larger. Pull it if your not going to be using the van for a bit.