Coolant overflow tank cap

[Aurelio corso]

I have a 1986 Comanche which has a cap that has a open and closed switch and was wondering why?and should it be in the closed position normally.

[eaglescout526]

Pics?

[Aurelio corso]

Can’t do pix.

[eaglescout526]

Alrighty then. It’s gonna be challenging for us to assist you. It sounds like you’re describing the windshield wiper reservoir. That has a sensor that goes to the cluster and tells you when you’re out of wiper fluid. 

[The86manche]

Where is it located specifically?

[Aurelio corso]

It’s on the coolant over flow plastic tank.

[eaglescout526]

Well if thats the case then you have a really rare part on your hands. If it is what I think it is, it is from an 84-85 XJ that had what was known as system sentry, it monitored the all fluid levels on the Jeep itself. It did not find its way onto 86 and newer models.