808_yukon
TYF Newbie
Hey guys doing a e fan swap and had a question on the wiring. I found a relay box at a junk yard from an 05 that has the 3 relays. From the videos I’ve watched 2 wires need to be pinned into the Ecm plug. C1 pin 42 is works out but c2 pin 33 has a wire already coming out and when I looked it up, it controls the hvac recirculating door. My question is do I just tap into that or cut and replace? My guess is tap in but I see some guys only running one wire to the ecm.
