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'05 Sienna Battery drain fixed

4.6K views 3 replies 4 participants last post by  Inites  
#1 ·
FYI...I have figured out what was causing my battery to drain on my '05 Sienna. This issue began about a year ago when the battery would go dead if motor not started after a week or so. I searched for the cause but never figured it out. The problem became much worse when the battery went dead overnight about 2 months ago. I took it into the Toyota dealership and they did a diagnostic and told me it was the terminals on the battery. This was NOT the problem. I then took it to a shop that specializes in electrical issues. They found the cause was the sensor at the rear hatch, it was not working properly and that kept the internal computer on (even though internal lights were all off), that's what was drawing power from the battery.

This is probably a result of excessive wear since I used this van for business and opened & closed the rear hatch quite often to access my tools.

BTW.... cost of a new rear hatch latch is $385 in case anyone needs one.
 
#4 ·
a parasitic draw test is the answer, the easiest way is go and buy and amperimeter clamp and chase down that stupid component, similar case happened to me with this stupid actuator never got to the point it should be so kept on trying to get there and eating battery.

I started at the battery itself to confirm primary current flow, then started pulling out fuses once i found that son of t$%&/( i grabbed again my clamp and measure wires related to that fuse and found that an actuator that closes it self when you lock the doors kept on working because it was damaged and never closed fully. then i just unplugged the actuator and that was the end, one cannot just pull out the fuse and drive because more than one circuits are fed with the same line.