Are you saying that, with the engine running and the AC controls set to "cold", you confirm refrigerant flow occurs in the sight glass, but the AC Condensor fans never come "on"?
Steve: With the engine running, the AC set on max cold and coolant flowing through the dryer sight glass, I can confirm that at least one fan comes on after the vehicle sits for about 8 minutes. I want to know if both are working (there are two, right?). Should one (both?) come on immediately when the AC is set to max cold? How does one access these fans in the 512TR? Is there a fuse/relay to check for power? Is there a thermostatic switch that commands the fan(s) to turn on? Sorry, I should have been more specific in the original post. I just replaced the compressor, dryer and expansion valve (Shamile lent a hand)and flushed out all the lines/condensor/evaporator and refurbished the evaporator with new foam, etc, and I want to make sure I have the whole system in optimum running condition before the onset of another Florida summer. ...Jim
Unfortunately, I don't have the wiring diagram for the 512TR so can't comment. No information (but the 512TR SPC does show 2 AC Condensor Fans). There's only one relay (relay "B"), but there could be a separate thermostatic switch in series with the second fan (although the delay to turn on the first fan shows there must be some form of thermal sensing going on) -- although they don't show it in the 512TR OM AC figure. A TR does have a thermostatic switch in series with its single condensor fan (but they do show the switch in the TR OM AC figure). Sorry I can't help, but maybe another 512TR owner can at least report what their AC condensor fan behavior is after turning the AC on.
