Driver Window Auto Control

The fact that the clock had to be reset and the driver's window auto function did not work is evidence that your battery charger did not provide 12V to the system while the battery was disconnected. This is to be expected.

Most battery chargers have a safety circuit that will disable the charger if it does not detect voltage produced by the battery. The voltage must be of the correct polarity and sufficiently high enough so that the charger thinks the battery can be charged safely.

Even if the battery charger did not have this safety circuit, it would still be a poor choice to provide 12V to the Prius. This is because the DC produced by a battery charger typically is very poorly filtered or regulated. A better choice to provide 12V backup would be a small 12V battery or a lab power supply which is both voltage and current regulated.

 

BTW, if you manually run the driver's window all the way down, then all the way up three times the computer will "re-learn" where the limits are and the auto function will magically return. I read that in a post on here somewhere. I had the same problem then noticed it worked again - the post explained all.

 

I had the same problem when I put my 12v battery back in. Thanks for explaining why this happened.

 

I replaced my 12v battery earlier today and window is working fine in auto mode, however when it's closed completely in auto mode it goes back down about 3-4cm. Now I have to roll it up manually. I know this car have safety but there is nothing caught between window and window frame. Hope this will go away. I looked in to manual and there was something about it but there is no fix for it in manual. Don't want to go to stealer.

P.S. This morning I was bragging on PriusChat that my 2004 12v battery was still good. That made me check my battery again and battery was bad ( 11.7v ) after car was running for about 40min so I picked up new battery from Toyota of Hackensack for $138.

 

Cycle the window full up and full down 3times ithink is the fixfor that.

 

Hi Patrick -

Most "consumer" battery chargers are rather low amperage, and one reason it's not recommended to use them to jump start.

Could this be a factor as well?

Thanks

 

The OP was just trying to keep powered up the volatile memory of various ECUs while the car was IG-OFF. The required current is ~30 mA, not counting any cabin lights that might be left on while you have the doors and/or the rear hatch open while swapping the 12V battery.

Hence I would say the the ampere rating is not a significant factor in the failure of the OP's attempt to use the charger as a backup 12V supply.

 

The three up and three down trick worked for me. Computers drive me nuts. Thanks for the tip. I got my Prius used from a Toyota dealership but they still couldn't come up with a manual for me.

 

3 times up & down didn't help, but this fixed my problem

 

$32.95 (but not the original press run). Or eBay....

-Chap

 

Thanks for the tip, been having the window issue as I'm trying to resolve full power off issues. Now I know why Auto UP/DOWN came back yesterday.... 3rd time through a drive-thru Thanks for saving me the time and worry over thinking I had an intermittent electrical issue with the driver's window switch. Know what to do for next time!

 

The backup beep resets also if you DC the battery. That applies if you had to changed to 1 beep by the dealer.

 

You can get a "memory saver" cord, plugs into a 12 volt socket on a jump pack, the other end into the OBD port. They work well, typically have an indicator light: if either end is plugged in, it'll light, to let you know it's found voltage. This way you know you're good before you disconnect your 12 volt battery.

Here's one example. Not the one I have, but they're all pretty similar I think:

Memory Saver Cord - ESA30 | Call us at 1-800-328-2921 | Clore Automotive

 

Thanks. The normal method of three cycles did not work. However the manual was correct.

 

We had this situation on our Prius 07 today. Halfway down and then back up, hold for a second!
Thank you for the information!