Hi all,
I am experiencing electrical lingo overload. I've read the related links and I am now thoroughly confussed. My Aux. fans are not coming on when "I think the should". With the car running and AC on full blast the "low speed" does not come on. I can see some foam through the "spy" glass on the receiver/dryer. I have been converted to r134 and did a recharge yesterday, I still see some foam (not sure if that means I have not filled it up enough?). As things stand now, I have cold AC. I jumped the two flat connectors coming off of the presure switch and the fans come on at low speed. Second (I forgot to write first above earlier), independent of the AC, as the car heats up, the high speed fans don't come on, the only way I have to measure temp is dash guage. I jump the temperature switch and the high speed fans come on.

I am trying to figure out what to do next. Is it safe to say that if the temperature switch is good (I replace it) then that should fix the high temp fan going on issue. And if I have the AC charged to the correct preasure (volume of refrigerant) and install a new preasure switch, I should be good on that one.

I guess what I am trying to figure out is, how do I test the two switches (presure and temperature) to see if they need to be replaced prior to doing anything else (spending any more money). I understand that in order for the preasure switch to work I need to correct charge in AC system.

I have an OHM meeter, never used it before though. Can I use that to test the switches?

Thanks a lot guys, without this forum I would never have gotten this far.

Joel