Hey all,
Over the last week or two I have been doing a lot of digging trying to find how to control electric cooling fans with the E78 ECM for a 2012 L96 6.0L LS. Since I have various resources and a LOT of time on my hands due to my job not always being very demanding I figured I would share what I was able to find.
On the E78 ECM, J1 Connector, pin 54 is fan 1 control and pin 41 is fan 2 control. Under this engine they are not called out as fan control on the list, they actually say not available, and you have to add pins to this location. However I found a thread under a chevy cruze 1.4L turbo, which also is supposed to use an E78, that suggested that these were in fact the correct pins. What I did was found other pins from the list that I knew I would never use, cut the wire so it had a pigtail coming from the connector and just relocated the pin, then butt connected an extension wire out the the pin in the fuse block.
On the Fuse block with 2012 chevy/ gmc truck, connector x2, Pin A1 is fan control low and Pin B5 is fan control high.
Also on the fuse block, Connector X1, Pins D1 and C1 are the power circuits that go out to the fans and each fan will need a ground. In the schematic I have attached, it shows the power to the fans wired differently, I did not try that route, but I am running electric fans not Pulse Width Modulated fans, therefore I want them either on or off. Not cycling power or giving varied voltage to the fans.
Attached is the full pinout that is called out for fuse block connectors X1 and X2. Where they are located on the bottom of the fuse block junction block, the wiring schematic and the J1 connector call out for the E78.
Please feel free to ask any questions you need!
Hope this helps some of your builds like it helped mine!
-Dan