[atwitsend]

Hi all,
Hoping for some help. This is what I have found and as my name implies I'm at my wits end.
Have power to the unit, even tried new unit and no luck.
Fuse is good
bought a relay and juggled it, got nothing.
Unplug TCS and fans come on high.
no fans if a/c is on
no fans if engine gets hot, but doesn't show as being hot either.
Any help much appreciated.

 

[atwitsend]

Replaced the Coolant temp sensor. checked all 3 relays, what I found is to the relays I am getting positive but not neg, I can ground to the frame and get voltage, but going off batt pos and relay neg I get nothing, going just relay I get nothing. So power is making it to the relays. I checked wire harnesses and all seemed good to go. Not sure where to check for the ground. Anyone have any insight?