Mystery connector behind lower central panel

Who doesn't like a good mystery?

I pulled off the lower central panel, the one containing the under-dash power point. Behind it, on the driver's side of the car, is a piece of raw steel tubing, maybe 20 degrees off vertical. Taped to that tubing is a 3-pin female connector, with black, yellow, and brown wires. It is plugged into nothing, and there is no matching male connector anywhere nearby.

Now, I freely admit I'm not good at reading vehicle wiring diagrams. It also may be less than helpful that the wiring diagram I have is for an '04, and my car is an '08. But I surely can not find any reference to this connector anywhere in the wiring diagram.

So what's it for? Is it for an option I don't have, or maybe a feature for markets other than the US?

Whoever solves this mystery gets 10,000 Internet points!

 

Oops, it't not taped directly to the tube. You can see it taped off to the other bundle, just above the wrap of blue tape.

Mystery_plug by egg_salad posted Jun 28, 2018 at 5:16 PM

 

My (admittedly limited) experience with Toyota wiring diagrams suggests that they use the same line drawings worldwide, and if nothing in the USA wiring diagram points to a certain connector, it simply isn't used in USA versions.

Edit: I looked at the connector diagrams. The only two natural (white) 3-pin connectors shown are B16 and O2. B16 goes to the passenger front Seat Buckle Switch and is in a completely different location. O2 is listed as "Option Connector (Glass Breakage Sensor)",

The latter is interesting. The diagram shows it in an entirely different location, but it is shown on Page 247 as having the correct color wires. Is it perhaps for a dealer- (or port-) installed alarm?

 

Aha! that makes sense with what I got from the wiring diagram!

 

Well, that's the location shown in the 2004 diagram for where the Glass Breakage Sensor should be. And the wiring colors are correct. What year car is in that photo? is it a 2008?

 

So the white connector towards the right of the photo is the 8-pin connector that Pashko spoke of. The foam-covered connector close to the center looks like it could mate to the connector I've found, but it's hard to say for certain.

What Pasko said also makes sense. The location for 04-05 would be hard to get to when adding the alarm, so it was moved to the new location for 06+ to make the sensor easier to install.

 

Here is a pinout of the 8-pin connector I found in a PDF of a troubleshooting manual:

VIP_connector by egg_salad posted Jun 28, 2018 at 7:13 PM

 

What I wrote above was that I found the reference to the Glass Breakage Sensor on page 247 of the 2004 wiring diagram. I found no reference to the alarm itself.

What I learned from poking around Google is that ALL G2 Prius have an alarm built in to the ECU. HOWEVER, it is not enabled by default. So if you requested an alarm from the dealer, that involved adding the GBS and going into the ECU via TechStream (or whatever other dealer software) and enabling the alarm.