The battery on my2007 Camry XLE V6 goes dead after 3 days of not being used. I've taked it to the dealership 3 times and they replaced the battery once but it still goes dead. They can't seem to find the problem. Any ideas as to what is causing this?

 

Could be an electrical power drain on the battery when ign off or a bad alternator.

After the engine has been off for 1 hour remove the positive battery cable and insert an amp meter between the cable terminal and battery. Make sure all electrical items off, doors closed , etc. The draw should be very low, around 50 milliamp.

Often the trunk light fails to turn off, the dealer should have checked this. An aftermarket installed alarm system can also cause problems.

The alt may not be working. Start the engine and idle at 1500-2000 RPM. Check the battery voltage, should be approx 13.5v-14.5 if the alt is working.

Does the car have a high capacity stereo amp or other power draining items?

The batteries current state of charge can be measured by using a volt meter across the battery terminals. Do this after engine has been shut down and battery rested for about an hour (not had any electrical load placed on it).

12.68v = 100% charge
12.45 = 75%
12.24 = 50%
12.06 = 25%
11.89 = 0%

 

Thanks for the information, I'll try checking this out. However, the Toyota dealer said they checked the alternator and it was fine. It seems to charge the battery if I drive every day or two but by the third day it is dead. I have no after market equipment on the vehicle and I keep the smart keys more than 30 feet away.

 

If the replacement battery is going dead after 3 days something is causing this. Surprised the Toyota dealer has not found the cause!

The alt can charge OK but if there is a drain on the battery it will go dead. Thus doing the test with the amp meter will determine if their is a high drain when the engine, etc if off.

One other issue is might read the owners manual. On older Camry equipped with the engine immobilizer theft protection system if the battery went dead or was disconnected the car would not start until the theft system was reset. If this is your situation make sure you know how to reset the theft system before disconnecting the battery.

If you don't have a problem with the theft system activating disconnect the battery when not using the car until the problem can be found. Yes a drag but will only take a minute or so. Repeated full discharge of a battery will kill it.

The have been strange cases where the computer was causing a battery drain, the alt had a bad diode which was causing a drain, after market theft system. If the battery has a parisitic drain problem you can remove fuses until it stops then track down the area.

 

The problem with my 2007 V6 Camry XLE battery seems to be ongoing. To date I have had the car into the Toyota dealership 18 times over the last year, each one lasting a full week. Toyota has replaced the alternator, two batteries, 2 body computers(what ever that is), the main computer, several relays and now say they are going to replace the speedo cluster. Does Toyota ever take a car back? Is there a way to approach Toyota with this issue and get some results? It seems that one of the hurdles is, I bought the car out of the US and live in Canada.

 

Just a guess, but check the cables not only on the battery but down by the alternator. A battery could technically last a couple of days with short trips, but eventually it would go dead. I had this issue with a bad alternator on a 1986 Honda Prelude...point is, if the battery is not getting recharged, it will eventually lack enough juice to turn over your car.