Hate to keep bringing this back up but...Last night I got a chance to do a little troubleshooting when I got home from work. Removed the panel under the passenger side dash and tapped the fan housing=nothing. Pulled the 2 pin plug from the fan and read it with my digital meter=0volts. Next I went under the hood and checked, starting with the #8 fuse=12.8VDC, pulled the wire off of the thermostat housing, inspected and re-attached, pulled the plug(2pin) from the mono valve, checked and re-attached. Back inside still nothing. I then shut the climate control switch off, then went to defrost. The fan came on. I again checked the 2 pin connector from the fan and read 12.8VDC. I then switched to the ECON setting and the Auto on the fan, and everything worked normal (vacuum pots switched to air ducts etc.). This morning (13 degrees outside) car started right up after glo plug light went out, no fan on defrost though. Went back inside to get ready for work and get a cup of coffee. When I came back out,(about 15 min.) still no fan. Switched system off, then to Defrost and the fan came right on. After the windshield was clear I switched to the ECON and everything worked. At lunch time today I went out. No fan, system still in ECON, about a mile down the road the fan kicked in and everything was working. I should add here that my temp gauge never gets much higher than 50 or 60 (Thinking I need a thermostat)
Questions- Where does the wire from the thermostat housing go? If I ground it, should I get voltage to the fan? Could that switch/sensor be bad? What about the wires on the Mono valve? What do they do and how can I check them? I'm thinking my problem lies in the electrical portion of the system under the hood but may still pull the CCU if I get time this weekend.
Thanks again,
Tom

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