My cooling fan hasn't been coming on since i smashed that deer last year. recently fixed...
fan relay bypass test - good
ecu control bypass - good
both the relay and fan work.

Stripped the wires from ECU... tried connecting them again. nothing
either the ECT isn't giving the ECU the info or the ECU isn't triggering the relay, or the wires are fubar. Also wasn't sure, heard about some A/C pressure switch, no clue. How can i test to pin point the problem?

Thermostat works, car won't overheat.
I got the idea to put a 12V 3 way switch in and ground it, then have it control the fan speeds. and it works. is this damaging? I'd rather clean fix

 

I believe there is a temp switch or plug in the block that could be bad.

 

Would there be a difference in ect or temp sensor between sedan N/A and wagon t5?

this is the part being referred to? http://cgi.ebay.com/ebaymotors/Volvo...item2c5016848e

I read over on MVS about a resistor, if this is what might have gone bad i have no clue as to where they're referring.
http://www.matthewsvolvosite.com/for...a702fa6d1af9d6