Mysterious Wire on a Tri-z

[hrc200x]

Anyone know where this wire goes? Its the brown one below the black box. I think the manual calls it a Br tube?

http://www.boreal.org/~kimball/ZwireBR.jpg

[hrc200x]

Anyone? Can someone go look on their Z?

[03 ORANGE SHEE]

brown goes to oil temp light on top of headlight!!!green is the other

[03 ORANGE SHEE]

i mean coolant temp!!!!!