my 2008 prius alarms goes off at odd hours after arming, it does not cease intill I put the key fob in the ignition and turn the car on, has this happened to anyone else? Any help here is greatly appreciated.
With car off measure the 12 volt battery dc voltage on the front jump point under the hood referenced to ground any bare bolt will work. With car still off then turn on the headlights in high beam for 5 mins. Shut off headlights with car still off wait one minute and then measure the dc voltage at the front jump point again Post those volt readings back here. You just did a load test on your battery to check its capacity to hold a charge as I suspect you have a soft 12 volt battery.. A healthy battery should not drop at all after this test. But....if you have ever had to jump start that 12 volt battery before don't bother with the test get a new battery.
