These harnesses include the gen ii lt1 lt4 gen iii 24x ls1 ls6 and vortec truck engines as well as gen iv 58x ls2 ls3 ls7 vortec and gen v lt.
Ls swap dual electric fan wiring.
Wiring dual cooling fans.
In this way the electric fan motors are wired in a series and voltage is reduced causing the fan motors to spin at low speed.
86 gray white wire goes to the ignition switch.
Crank spacer is a bit of a misnomer.
Some 2003 ls pcm s tach signal is not strong enough and needs boosted see this link.
Electric fan guide 100 horsepower anybody can install in gen 3 ls.
30 other red wire needs constant 12 volt power from the battery.
85 black wire.
This is based on the draw from the fans if the fans are larger and draw more than 15 amps each it s recommended to install a second relay kit as shown below.
Https amzn to 377klrp those fans fit perfect on 68 72 gm a body cars bu.
87 red wire connects to the positive wire on the electric fan.
Fan controls 1 2 gm pcm s typically will control electric fans usually 2.
Your 1 source for oem operated pcm controled and universal electric fan harnesses.
The pcm will supply the negative or ground signal to turn on fan relays.
In this way the electric fan motors are wired in parallel causing the fan motors to spin at high speed.
When the pcm triggers the two additional relays the same voltage flows through each electric fan motor.
Thank you to all that stuck with us during this hectic time.
This applies to all transmissions that were originally used prior to the introduction of the ls platform around 1999.
Most builders are familiar with fabrication techniques trouble shooting and parts swapping to make things work but electronics rise to a much higher level of complexity.
So your th350 th400 700r early 4l60e early 4l80e etc will need to have one of these crank spacers.
You can not directly connect pcm fan control wire to fans.
Upgrading to gen iii ls series pcm.
With dual cooling fans there are two methods for wiring up the relay kit.
Just an idea on how to wire up electric cooling fans for your vehicle cooling fans.
You must use a relay.
The wiring aspect of any ls swap is undoubtedly the most difficult.
Psi sells standalone wiring harnesses for gm gen ii iii iv v ls lt based engines and transmissions.