Last night, reading in the car (2005) waiting to pick up my daughter after a party, slightly dodgy part of Hollywood, locked the doors. Battery went dead. Don't know why, since I was reading on my computer, no interior lights on, nothing. Whatever. Called AAA. They came, I opened the door (presumably with alarm still on though dead), popped the hood, they hooked up, started car. All fine. I drove around to keep the car running until daughter emerged. Went home, no problem. Parked. Walked away. Alarm goes off. Turn it off. Walk away. Alarm goes off. Somehow get it to stop. Sleep. This morning, have to move car so wife can get out. Park on street. Lock it. Alarm goes off. Doesn't want to turn off. Much button pressing. Turns off. Get out, car unlocked, unarmed. Alarm goes off. The only way I can get the alarm not to arm (and then go off) is to leave the key-fob in the slot. Manual says if the battery is disconnect while the alarm is armed, the dealer has to turn it off. It's Sunday. Our neighborhood is okay, but I don't love leaving the car unlocked with the key it in it. Any suggestions?
What your experiencing I think is a low boot battery. The one you jumped. When that goes low volt it does all kinds of wacky things. It must be replaced asap. In fact even if it did not exhibit the key fob issue it needs to be replaced. Your way overdue anyway. That battery is almost 7 years old. Search for "optima" battery. The yellowtop. Its the best bet. Most people buy them from eLearnaid as it will come with a connection kit. Or your at the dealer mercy which ranges for $200 to $300 installed. I would leave the key fob in the car and lock the door manually with the mechanical key included inside the fob. Just put a piece of tape over the key fob so no one can see its in the holder. Good Luck.
I suspect your ECU got into a funny mode. Try disconnecting the negative battery terminal for a few minutes. That should reset everything. If that does not work, send me a PM with your email, and I will send you the alarm repair manual.
Thanks for the offer. I think I'm better able to take the car to the dealer. Me and an alarm repair manual? Not a match made in heaven! Thanks, though, for the time and the offer. I appreciate it. Cotty
Dealer pass/fail testers can sometimes incorrectly pass a Prius 12V battery. You can easily check the 12V battery yourself using this procedure: http://priuschat.com/forums/newbie-forum/73400-weird-stuff-happening-mpgs-dropping-test-battery.html In future avoid the problem. Whenever you want to sit in the car for more than five minutes using any accessories, put it in Park and leave it ON. Then it takes care of its own batteries exactly as it was designed to do.
Try pulling the dome fuse under the hood for a minute. Resets everything. Right side of the engine, black box with a cover. Fuse puller there too. I did that when my inside lights got left on and battery kind of dead left things in a funny state. Like said above it got in a funny (or not funny) mode. Or, yes go to the dealer. Could be first indications of a battery going bad.