
Originally Posted by
TRPLXL2
I put a set of 4th gen F body fans in my 04' Colorado, I bought a set of relays and have been messing with them for two days now. I can't figure out how they are supposed to be wired up, hope somebody can save my sanity, I am slo using the ECM to control the fans. (green wire and blue wire from PCM)
Relay diagram Instructions
orange- relay coil feed (applying voltage to this wire activates the relay coil.)
Black- grounds relay coil
Blue-normally open (has continuity with common red wire with voltage applied to relay coil feed orange wire)
Brown- Normally closed (has continuity with common red wire with "NO" voltage on relay coil feed orange wire.
Red- Common with blue or brown wire depending on voltage present on coil feed orange wire.
I had the black wire grounded to battery, red wire direct to + of battery with 30 amp fuse, brown wire I wasn't using, blue wire I had to + of fan, orange wire I had to the ECM wires. I grounded the - of the fans to the battery as well.
I can't get the fans to come on via ECM signal, after researching tonight I found out the ECM signal is actually a ground, so that is one mistake I made so far. I tried several ways of hooking them up, and could not get them to work correctly.....