so i got my new hoses installed and system charged. ready to turn on the ac but i need my efans to kick on high speed durring operation. Im looking for the best way to do this.
a few options are...
1) hook ac control wire to PCM
- This will have to be done after i find someone with the correct software to change the pcm port to discrete instead of class 2 data. so this option is out for now
2) hook ac control wire to a relay. that realy when actuated will supply a ground to the relays that the pcm would normally supply a ground to for high speed operation
3) using the aux cooling fan AC pressure switch which is in the condenser already. from the drawing, it looks like it just supplies a ground also. which would serve the same purpose as option 2 but with a heck of a lot less wiring and one less relay to add.
but im confused on how that switch works. im assuming when the ac pump is engaged and pressure starts building, this switch closes and will kick the fans on??? does it cycle on and off? should my fans be running on high constantly as long as the ac is being called for reguardless if the pump is engaged or not?
and why do i have this switch in the condenser but my truck originally came with a clutch fan and there is no relay for aux fans in my fuse block...??? did GM really install it for a "just incase" upgrade or is this switch something completely different?
this is the switch im talking about
and this is how i have the fans hooked up now. ill just need to tap into the wire coming from pcm to the two high speed relays. i will also install a diode to prevent backfeed to pcm.
not sure the best way to do this. thanks.
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