I have a package #1 prius 2008 and successfully enabled the factory alarm. All 2006-2009 prius have a factory alarm built in. You have the option of purchasing the useless glass breakage sensor for 50. And putting that in too. But who wants false alarms? There are two ways to do this: 1. Visit the toyota stealership and ask them to do this. Unfortunately the 3 dealers I contacted in the Bay Area did not know what I was talking about. 2. Order the techstream software and cable off ebay for $20-$30. (hong kong/china vendor-make sure it includes techstream) And do it yourself. Locate the instructions for the gbs. Which tells you how to enable the alarm in the prius. Here's a link to the pdf. Get it before the link is dead http://toyotapart.com/08586-47841.pdf
