05-06 Escalade Wiring Diagram Needed...Cooling Fan & Relay Block

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

gpracer1

Full Access Member
Joined
Jun 16, 2011
Posts
910
Reaction score
360
Location
Phoenix
Hey guys I was wondering if anyone has a wiring diagram for an 05-06 Escalade that shows the cooling fans and the relay block so I can wire mine up to my 99. I know its not plug and play, but Im going to make my own version as soon as I find out how the relays are wired. Thanks.
 

ScottyBoy

Full Access Member
Joined
Jun 27, 2010
Posts
2,565
Reaction score
1,723
Location
Shreveport, La
Here you go.

efan.jpg

If you are using a stock relay harness and fans from an 05-06, then you simply need to hook the fat red wire to the battery, the two ground wires to ground, and the blue and green are your negative trigger wires. Blue turns on the right fan on high when it is grounded. Green turns both fans on low when it is grounded. If the blue and green and both grounded at the same time, then both fans will turn on high.
 
Last edited:
OP
OP
gpracer1

gpracer1

Full Access Member
Joined
Jun 16, 2011
Posts
910
Reaction score
360
Location
Phoenix
Here you go.

efan.jpg

If you are using a stock relay harness and fans from an 05-06, then you simply need to hook the fat red wire to the battery, the two ground wires to ground, and the blue and green are your negative trigger wires. Blue turns on the right fan on high when it is grounded. Green turns both fans on low when it is grounded. If the blue and green and both grounded at the same time, then both fans will turn on high.

Awesome man, thanks.
:Handshake:
 
OP
OP
gpracer1

gpracer1

Full Access Member
Joined
Jun 16, 2011
Posts
910
Reaction score
360
Location
Phoenix
Now I see how they did low speed without any resistors. When the green is grounded it puts both fans in series so they only get 6 volts each.
When the two blue wires which are connected are grounded, each fan gets its own 12 volts.
 

ScottyBoy

Full Access Member
Joined
Jun 27, 2010
Posts
2,565
Reaction score
1,723
Location
Shreveport, La
Correct, if the blue wire is grounded then both fans are wired in series therefore turning them both on low. If the green is grounded, the right fan turns on full speed. If the blue and green are BOTH grounded then both fans will turn on at full speed.
 
OP
OP
gpracer1

gpracer1

Full Access Member
Joined
Jun 16, 2011
Posts
910
Reaction score
360
Location
Phoenix
Correct, if the blue wire is grounded then both fans are wired in series therefore turning them both on low. If the green is grounded, the right fan turns on full speed. If the blue and green are BOTH grounded then both fans will turn on at full speed.

I think you have the blue and green reversed.
Looks like the green runs both and the blue just one......ground both and they both run high.
 

ScottyBoy

Full Access Member
Joined
Jun 27, 2010
Posts
2,565
Reaction score
1,723
Location
Shreveport, La
I think you have the blue and green reversed.
Looks like the green runs both and the blue just one......ground both and they both run high.

Yeah, you caught me. I typed that wrong. Lol.
I have the Blue tied to my AC clutch wire and it turns on the right side fan when the AC is on. The green is tied into pin 42 of my PCM and is grounded when the temp gets to 209, and turns both fans on low if the AC is off and both on high if the AC is on.

See my install thread, this is how I installed my fans and harness.
http://www.tahoeyukonforum.com/forum/showthread.php?t=28336
 

bottomline2000

Full Access Member
Joined
Oct 21, 2009
Posts
1,722
Reaction score
987
Location
Dallas, TX
faulty fans?

Yeah, you caught me. I typed that wrong. Lol.
I have the Blue tied to my AC clutch wire and it turns on the right side fan when the AC is on. The green is tied into pin 42 of my PCM and is grounded when the temp gets to 209, and turns both fans on low if the AC is off and both on high if the AC is on.

See my install thread, this is how I installed my fans and harness.
http://www.tahoeyukonforum.com/forum/showthread.php?t=28336

Scotty you seem to be somewhat of a wiring guru. I was wondering if you could give me some ideas of why my fans default to low when the truck is running. They do not turn on with just ignition, only when the truck is running. When the a/c turns on the fans cycle to high when the compressor engages. I've disconnected the left fan and just run the truck with a/c and the right fan engages with the compressor to high and cycles off as it should.

I'm at a loss. I've replaced everything possible, switched ECMs, changed the wiring harness from BB to a Nelson one, changed the coolant temp sensor and same problem. I'm running OEM fans from a 05 Yukon. The fans seem to have a high amp draw even with my built alternator. I'm currently running my stock 130 amp alt with the overdrive pulley from blackbear, but the amp draw is still noticable. Is it possible for the fans to back feed and trigger the relay?? and if so how can I test this? fans are the only thing I haven't replaced lol..so I've done this mod twice!!

again, I've seen your write ups and you seem to be on point with electrical.. hoping you can help me out or point me in the right direction.. I also have a brand new radiator and fresh coolant to eliminate even one more thing..
 

ScottyBoy

Full Access Member
Joined
Jun 27, 2010
Posts
2,565
Reaction score
1,723
Location
Shreveport, La
They should only turn on when the temp gets up to over 200 degrees. Double check that you have the wire in the correct pin. And was you PCM properly tuned for Efans?
 

bottomline2000

Full Access Member
Joined
Oct 21, 2009
Posts
1,722
Reaction score
987
Location
Dallas, TX
Yeah I have quadruple checked the pin cinnection. Only one spot open for blue pin 42. I had my tune done live by Justin and he even sent a backup PCM to make sure. Don't what it could be.
 
Top