2 speed electric fans for LS swaps on the cheap

[@queezytarantino1456]

Hey, do you have a wiring diagram for the cooling fans to 3 relays?

[@hackjobhotrodshop5075]

I don't, why would you want 3 relays? Lots of fans?

[@queezytarantino1456]

@@hackjobhotrodshop5075 the stock ls fans I had were controlled by 3 relays.

[@ajsgarage3471]

Did you hard wire the fans or use the factory connector from the intrepid? When I give 12v to from car battery it's not blowing as well as yours. Seems like it's hard speed with direct power to battery. With my 24v impact drill battery they blow very strong. Any idea why it blows harder with drill battery versus car battery?

[@hackjobhotrodshop5075]

Did you wire up both the high and low speed coil of the motors? If you only wire up one side it will spin low, both it will spin fast.

[@ajsgarage3471]

How do I wire up the high and low speed for each motor?

[@hackjobhotrodshop5075]

@@ajsgarage3471 One output from the ECU goes to a low speed relay and the other output from the ECU goes to a high speed fan relay. Each relay output connects to 1 lead of the fan, low is yellow, high is green.

[@ajsgarage3471]

Before I hooked up the relays I tested the fans both black wires to ground yellow or green to positive I get a very low speed green and yellow both to positive I get a medium the fans are switching between low and high but not blowing good to reduce temperature when I apply 24v from drill battery to green or yellow or both they blow like a tornado with a regular 12v car battery they don't any idea why?

[@curtthompson2787]

How is this on the cheap? Adding parts. Whats cheaper about it vs. others? And especially when youll have to guy a $400+ scan tool?

[@hackjobhotrodshop5075]

You can do it on a $1000+ aftermarket standalone ECU. If you are using an OEM harness on a swap you needed to unlock the computer anyway so the fan program is free as part of rest of the program. Plus a $3 relay.

[@dlawson8993]

Will this work with a two speed fan with high and low?

[@Cambo540]

I’m struggling getting these to work correctly to relays. Do you have the diagram that you used? Thanks.

[@hackjobhotrodshop5075]

lt1swap.com/wiringharness.htm

[@Cambo540]

@@hackjobhotrodshop5075 thanks for responding. I followed his diagram but having trouble with the it only working on low speed when I test them on the bench. Did you have that problem also?

[@hackjobhotrodshop5075]

What fan are you using? Is it a 2 motor or dual coil fan? Is the HPtuners setting correct? Çan you use a volt meter and see if the ecm is grounding the pin you want?

[@Cambo540]

@@hackjobhotrodshop5075 they are the exact same fans you have, the ones without the relays from the factory. I am just testing them with a drill battery and whenever I ground either or both wires that will wire to the PCM, it stays the same speed. Thanks for your input so far. Let me know if you think of anything else. Maybe I’ll have to see when I start tuning with HPtuners.