I have 2 speed dual fans; lo and high.
I've heard that the proper way to wire these 2 speed fans is to have the #1 fan signal (say at 200 degrees) from the PCM trigger BOTH fans at low speed simultaneously; and then the #2 fan signal (say at 205 degrees) from the PCM trigger both fans simultaneously at high speed (rather than just trigger each fan separately).
This is obviously different than single speed fans where the #1 fan signal from the PCM triggers the relay to provide 12v to the #1 fan at 200 degrees (in my example) and the #2 fan signal from the PCM triggers the relay to provide 12v at 205 degrees (in my example).
Thanks in advance.