How do you replace a 1999 Toyota Sienna car battery and not have the alarm sound when plugging in new battery?

Answer 1

There is no way that I know of to prevent the alarm (which is the horn going off) from sounding when you install a new battery (or when you disconnect and reconnect a battery) into the 1999 Toyota Sienna. However, to get the alarm to go off (to shut off--stop sounding) you only need to "re-set the system". I do not know the exact combination of "key cycling" (turning the key on and off and on again), and button pushing (there is a red lighted button on the left side of the drivers dashboard), but if you do it the alarm with shut off.

The combination as told to me by a Toyota repair tech and a salesman is something like one or two button pushes to a ignition key cycling to one or two or three button pushes.

I did this this morning (Sep. 24, 09) and by just randomly trying button pushes and key cycling I was able to get the alarm to shut off and get the van started. The van operates properly now. I hope this helps, it was driving me nuts that no one knew the exact combination. I am still looking for it.
Mark