AC and dual "fans on" one or two relays?
I'm trying to understand how to activate dual fans with AC.
I have an E38 PCM and a SPEARTECH harness, Vintage air and dual fans.
Speartech calls for fan One and fan Two. the harness has dedicated 12v + (keyed) and ground (switched) signal for each fans.
So when I add AC now I need to activate both fans at AC on through trinary switch.
When I contacted speartech they said to split the AC on signal to each relay.
My concern is that when I combine both relays to the one AC on signal that I am essentially tying the fan one and fan two signal from the pcm together and both fans will come on when just fan one is activated by pcm.
My thinking is that I will need two additional relays to keep the signals separated, correct?