Resetting your 12V battery

There is basically one battery code that can prevent you from starting the car.  It's a P0AA6, and I see it quite a bit more than I like.  I'm confident it has to do with the extreme heat in AZ.  I collaborate with others doing similar work in other regions, and P0AA6 codes occur 5-10X as much here in Phoenix.

A P0AA6 is a high voltage leak.  Basically, somewhere in the car, the computers are sensing a high voltage path to the body ground where it shouldn't be.  This can occur in the HV Battery (most common), in the A/C compressor (next most common), the transaxle (you pray it's not this one), the inverter (again, a little prayer is in order, but at least a salvage replacement won't completely break the bank) or the harness (shoot me please).

Once P0AA6 occurs, you are allowed to drive once more until you turn the car off.  Then you are dead in the water. This disabling is a safety feature.

In an emergency, you can disconnect your 12V battery, reconnect and wipe the code.  You will then be able to drive one more time.

The following video shows you how to access the 12V, remove the maroon cover at 1:04 and disconnect the first plug only at 1:09:

https://www.youtube.com/watch?v=L_b4u5jChds

We are not affiliated with this youtuber.

Leave it disconnected for two minutes. This removes power from the dozen+ computers in the car and will clear most codes. Reconnect, and you should be able to make one more drive.

NOTE: After a 12V disconnect, the power button must be pressed two times to get it to show read. Depress the brake pedal, hit the power button, wait 2-3 seconds and hit it again. It should go into ready mode.  This is discussed in your owner's manual.  For the 2004, it's on page 231 in the NOTICE block.

You can access your owner's manual online here:

https://techinfo.toyota.com/techInfoPortal/appmanager/t3/ti?_nfpb=true&_pageLabel=ti_home_search_docs_page

Once the car is in ready mode, it should drive normally until the HV leak is detected again. Proceed to your final destination driving conservatively.  If you go to an auto parts store to get your codes checked, make sure you leave the car in ready mode!  Don't turn it off!

If the P0AA6 is traceable to the HV battery, we can certainly help!