Temp heat switch wire is connected to my temp sender?

[banderberg]

Engine is Merc 3.0L. Looking over the service manual, it shows that I should have the tan wire running from my sender to the gauge. and the tan/blue wire running from an optional audio warning water temp heat switch. Instead, my engine has both the tan and the tan/blue wires running from the temp sender. I know the tan wire goes to my gauge, but have not verified where the tan/blue wire is going. Any idea why the tan/blue wire would be connected to my temp sender?

 

[alldodge]

Someone moved it would be a guess.
Don't know your serial number but both the switch and sender should be real close to one another on the thermostat housing

 

[Bondo]

Engine is Merc 3.0L. Looking over the service manual, it shows that I should have the tan wire running from my sender to the gauge. and the tan/blue wire running from an optional audio warning water temp heat switch. Instead, my engine has both the tan and the tan/blue wires running from the temp sender. I know the tan wire goes to my gauge, but have not verified where the tan/blue wire is going. Any idea why the tan/blue wire would be connected to my temp sender?

Ayuh,..... To answer the question ya asked in that antique thread,.....
The t-stat gasket needs the brass crush rivets to properly ground the housin', so the sender, 'n switch will work,.....

 

[banderberg]

Someone moved it would be a guess.
Don't know your serial number but both the switch and sender should be real close to one another on the thermostat housing

It's 0D389001 - I am pretty sure I do not have a temp switch.

 

[alldodge]

OK, your motor could be either one piece manifold, or manifold with end caps, and none have a temp switch only temp sender. I would disconnect the Ten/Blue and tap it.

You could install a NPT Tee and install both