What doe these things do?

[Stainless]

While replacing the clutch slave cylinder, it appears that I have broken a couple of things, but I'm not sure what they do. One is a wire and the other is a very thin plastic tube. Your help is appreciated.

This is the wire that has been pulled out of the connector:
http://i173.photobucket.com/albums/w57/jlattin21/DSCN0363.jpg

Here is the plastic tube that is broken. It appears to have been rigged together by the previous owner:
http://i173.photobucket.com/albums/w57/jlattin21/DSCN0364.jpg

This picture shows the two from under the car. The plastic tube connects to the object that is framed in the red square in the picture below. The circled wire is the broken one in question as well.
http://i173.photobucket.com/albums/w57/jlattin21/Dcord.png
I can't find either of these parts in the parts manual to figure out what they do. Thanks for your help.

[sdg3205]

The broken tube is the vacuum line for your heater valve.

The plug looks like the reverse switch lines, but a pro might know better.

[Jonathan]

Is that second picture wire with the tube/insulation wrap on it disappearing through the pontoon the wire going to/from the O2 sensor?

[opethmike]

The plastic tube going into the firewall in that second picture is for the heater control.

[Stainless]

May be a dumb question, but what does the heater valve even do? What does it need a vacuum line for?

[dmc6960]

The heater valve shuts off the hot water flow to the heater core when the mode switch is on the MAX setting for the air conditioning. Vacuum activates it, it is normally open.

[Nicholas R]

The heater valve shuts off the hot water flow to the heater core when the mode switch is on the MAX setting for the air conditioning. Vacuum activates it, it is normally open.

+1

Essentially its the only difference between the normal AC setting and the MAX AC setting. MAX keeps coolant from circulating the heater core thereby keeping the area under the dash that much cooler.

[jmettee]

The broken wire/harness is the wire running to the diagnostic plug. Car will run without it. You can essentially unplug the connector & remove the diagnostic plug & mount if you want to (note it's also connected to the magnetic pickup from the flywheel). FYI, the diagnostic plug is in the red circle below & effectively doesn't do anything at all since there is no device known that plugs into it.

7978

[Ron]

Essentially its the only difference between the normal AC setting and the MAX AC setting. Perhaps more important is the air recirculation flap is opened/closed also. (fwiw ;-)

[Stainless]

Thanks for all the info, guys. That is crazy that the diagnostic plug doesn't do anything. Why is it there in the first place?

The vacuum line was definitely already broken by a previous owner; hence the small tubing to reconnect them. I just happened to discover it by accident when a wrench fell on the line and pulled them apart. The tubing doesn't seem nearly tight enough to allow a vacuum connection to form. I may put some sealant around the edges of the rubber tubing to allow the plastic tubing to do the job it is intended for.

Thanks for helping identify this stuff for me.

[Ron]

Thanks for all the info, guys. That is crazy that the diagnostic plug doesn't do anything. Why is it there in the first place? Probably just for the factory/dealers??

Might me my crappy monitor, but the colors for the two wire plug look different in the pic than mine (an auto)... but if I have the right wires/end, they aren't useless.
IIRC, the orange wire is good for dwell (pin 17 on the lamda ECU), and the other (Pink on mine) is 12V from fuse #12.

[DMC5180]

I believe the Diagnostic plug was a leftover from Volvo. I know someone who has a "SUN emission/diagnostic machine" that supposedly plugs into it. I believe it was quick way for the factory and/or California Emissions inspectors to do CO adjustment and set "Lambda". Never quite understood the need for the Magnetic pick up at the flywheel though. Unless it was an isolated way to read RPM with the SUN machine Tach.

I'm sure Dave S. will chime in and clarify things though.