I also own a 2006 Highlander Hybrid and have been reading the "VIN break" info posted by a person who goes by the forum alias "Maryland John" in various forum sites across the internet. I believe this person deduced the "VIN break" from answers provided through an expert online subscription site (see link below). The Toyota expert he interacted with never exactly said that the set of VINs provided are considered "VIN break" for determining whether a HiHy is at risk for inverter problem. The expert just said that new version of the inverter was installed on a HiHy after certain VIN. So the "VIN break" is a result that a person subjectively jump to conclude and is not something that was really stated right out by the Toyota expert. So I think you have to take the info with a grain of salt, in my opinion.
You can find the entire length of the person's discussion with the Toyota expert at the URL below (Go to bottom of page at the section named "Accepted Answer" and click on the "Read the entire conversation" link on the right side):
http://www.justanswer.com/questions...rid-inverter-failures-in-the-2006-highlanders
You can find the entire length of the person's discussion with the Toyota expert at the URL below (Go to bottom of page at the section named "Accepted Answer" and click on the "Read the entire conversation" link on the right side):
http://www.justanswer.com/questions...rid-inverter-failures-in-the-2006-highlanders