...

Go Back   Lateral-g Forums > Technical Discussions > Cooling: Radiators/Fans/Controllers
User Name
Password



Reply
 
Thread Tools Display Modes
  #1  
Old 11-19-2018, 12:14 PM
Gmachine1911's Avatar
Gmachine1911 Gmachine1911 is offline
Senior Member
 
Join Date: Oct 2017
Location: Southern IN
Posts: 472
Thanks: 65
Thanked 373 Times in 250 Posts
Default Question: LS3 fan control wire; power or ground?

I’m looking at purchasing the Entropy fan controller but I do not want to run their secondary temperature sensor. On my LS3 crate engine with the GMPP harness, does the single blue fan wire send 12 V or a ground signal? I’m sure. this has been covered in depth already but after numerous searches, it is evading me. Thanks!
__________________
Shane
#theanchorholds

Link to my 68 Camaro build thread:
https://lateral-g.net/forums/showthread.php?t=56387

Link to my 67 Nova build thread:
https://lateral-g.net/forums/showthread.php?t=57769
Reply With Quote
  #2  
Old 11-19-2018, 02:13 PM
dontlifttoshift's Avatar
dontlifttoshift dontlifttoshift is offline
Senior Member
 
Join Date: Oct 2012
Location: Beach Park. IL
Posts: 959
Thanks: 16
Thanked 175 Times in 103 Posts
Default

The big fat blue wire is power. It comes from the fan relay in the fuse box. That relay is computer controlled.
__________________
Donny

Support your local hot rod shop!
Reply With Quote
The Following User Says Thank You to dontlifttoshift For This Useful Post:
pannetron (10-05-2019)
  #3  
Old 11-19-2018, 08:15 PM
dhutton dhutton is offline
Senior Member
 
Join Date: Nov 2006
Location: Mountain Springs, Texas
Posts: 1,892
Thanks: 1,097
Thanked 484 Times in 267 Posts
Default

Quote:
Originally Posted by Gmachine1911 View Post
I’m looking at purchasing the Entropy fan controller but I do not want to run their secondary temperature sensor. On my LS3 crate engine with the GMPP harness, does the single blue fan wire send 12 V or a ground signal? I’m sure. this has been covered in depth already but after numerous searches, it is evading me. Thanks!
You won’t get two speed fans if you don’t use their sensor.
Reply With Quote
  #4  
Old 11-19-2018, 08:51 PM
Gmachine1911's Avatar
Gmachine1911 Gmachine1911 is offline
Senior Member
 
Join Date: Oct 2017
Location: Southern IN
Posts: 472
Thanks: 65
Thanked 373 Times in 250 Posts
Default

Quote:
Originally Posted by dhutton View Post
You won’t get two speed fans if you don’t use their sensor.
Yeah, that's the downside. According to Frank at Entropy, unless you wire the yellow wire to a ground activation, or use their sensor, you won't get the "two speed" function...at least not when the high/low fan wires are joined in the GM fuse box. Bummer cuz I like their setup.
__________________
Shane
#theanchorholds

Link to my 68 Camaro build thread:
https://lateral-g.net/forums/showthread.php?t=56387

Link to my 67 Nova build thread:
https://lateral-g.net/forums/showthread.php?t=57769
Reply With Quote
  #5  
Old 11-20-2018, 12:07 AM
randy randy is offline
Senior Member
 
Join Date: Jan 2011
Posts: 1,041
Thanks: 3
Thanked 68 Times in 43 Posts
Default

http://www.gm-efi.com/news/pcm-ncs-g...ctric-fan-kit/

Works like a charm
Reply With Quote
The Following User Says Thank You to randy For This Useful Post:
1965_SS (11-30-2018)
  #6  
Old 11-20-2018, 08:04 AM
Gmachine1911's Avatar
Gmachine1911 Gmachine1911 is offline
Senior Member
 
Join Date: Oct 2017
Location: Southern IN
Posts: 472
Thanks: 65
Thanked 373 Times in 250 Posts
Default

Quote:
Originally Posted by randy View Post
Thanks, Randy...I checked that out early on but was intimidated by the prospect of messing with the ECM. Also by the fact that that fuse box is a total PITA to try to open up! I don't own HP Tuners so would I have to send them my ECM? It's also my understanding that I'll need the AC bump harness as well. I like the fact that it's 100% integrated and all relays, fuses, etc. will by in the engine fuse box.
Any insight on getting to the inside of the fuse box as well as the ECM side would be most appreciated!
__________________
Shane
#theanchorholds

Link to my 68 Camaro build thread:
https://lateral-g.net/forums/showthread.php?t=56387

Link to my 67 Nova build thread:
https://lateral-g.net/forums/showthread.php?t=57769
Reply With Quote
  #7  
Old 11-20-2018, 08:28 AM
DT69Cam DT69Cam is offline
Senior Member
 
Join Date: Jan 2016
Posts: 213
Thanks: 2
Thanked 2 Times in 2 Posts
Default

Quote:
Originally Posted by Gmachine1911 View Post
I’m looking at purchasing the Entropy fan controller but I do not want to run their secondary temperature sensor. On my LS3 crate engine with the GMPP harness, does the single blue fan wire send 12 V or a ground signal? I’m sure. this has been covered in depth already but after numerous searches, it is evading me. Thanks!
I purchased the Entropy LSX fan controller kit. Super easy to install. Plug and play essentially. Absolutely love the 2 speeds. I did not use the GMPP blue wire. I just capped it off. I'm also using their radiator.
__________________
69 Camaro Convertible (LS3/TKO in the works)
Reply With Quote
  #8  
Old 11-20-2018, 09:16 AM
randy randy is offline
Senior Member
 
Join Date: Jan 2011
Posts: 1,041
Thanks: 3
Thanked 68 Times in 43 Posts
Default

Quote:
Originally Posted by Gmachine1911 View Post
Thanks, Randy...I checked that out early on but was intimidated by the prospect of messing with the ECM. Also by the fact that that fuse box is a total PITA to try to open up! I don't own HP Tuners so would I have to send them my ECM? It's also my understanding that I'll need the AC bump harness as well. I like the fact that it's 100% integrated and all relays, fuses, etc. will by in the engine fuse box.
Any insight on getting to the inside of the fuse box as well as the ECM side would be most appreciated!
Someone in your area has to have HP tuners and if so its really easy to upload. Opening up the fuse box is simple as well. Instructions in the kit were very easy to follow. I purchased the AC bump kit as well which instead of connecting the AC bump by the ecu just connect it to the wires you are already messing with when working with the dual fan kit. In in all it took me about 45 min to install and everything works OEM. This will clean up all of your wiring for your fans and you will love it.

Wish you were closer i would just help you out
Reply With Quote
The Following User Says Thank You to randy For This Useful Post:
Gmachine1911 (11-20-2018)
  #9  
Old 11-20-2018, 06:13 PM
Gmachine1911's Avatar
Gmachine1911 Gmachine1911 is offline
Senior Member
 
Join Date: Oct 2017
Location: Southern IN
Posts: 472
Thanks: 65
Thanked 373 Times in 250 Posts
Default

Alrighty, pulled the trigger on the PCM of NC fan harness and AC bump kit setup. Spoke with them on the phone and they sent me their instructions to check out prior to ordering. Other than the fact that you have to splice into a couple of the ECM connectors (which scares the crap out of me) this should be a slick setup. Even at that, the instructions are very detailed about where to make the connections both inside the engine fuse box and the ECM connectors.

Randy, I appreciate your input on the matter and certainly the offer of help! One question I have for you is that, if I understood PCM correctly, there's no need to run a trinary switch with this setup since the ECM/fans get the signal to activate or speed up directly from the AC compressor itself, correct? If that's the case then that will further decrease the wiring in the front of the car.
__________________
Shane
#theanchorholds

Link to my 68 Camaro build thread:
https://lateral-g.net/forums/showthread.php?t=56387

Link to my 67 Nova build thread:
https://lateral-g.net/forums/showthread.php?t=57769
Reply With Quote
  #10  
Old 11-20-2018, 06:53 PM
randy randy is offline
Senior Member
 
Join Date: Jan 2011
Posts: 1,041
Thanks: 3
Thanked 68 Times in 43 Posts
Default

Binary switch

All the wiring is inside the fuse box. You don’t need to touch any connectors. When you get the kit and your ready to start the wiring I will walk you thru it since I still have my instructions.

Bottom line is you have two wires going to the one relay. I think blue and green. You cut one and then reroute it to your new relay. You give that relay some power, fuse it, and add a line out. Now your fuse box has two line outs. The wire that you tap into for the AC bump you are already working with the new dual fan kit. Tap into it at the fuse box and some other wires. Trust me it’s really easy once you start messing with it.

When you get the kit just text me at 972-814-8824. Maybe when I have some free time I’ll dig my instructions out and just make a diagram for you
Reply With Quote
The Following User Says Thank You to randy For This Useful Post:
RdHuggr68 (11-20-2018)
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 01:41 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright Lateral-g.net