ScottyBoy
Full Access Member
Wow, that's a REALLY good price! And then add in the fact that they even pulled them too? Plus all the wiring, that's really a steal. The fans alone usually sell for around $100 at most yards.
Electric fans enough for 3/4 ton XL that tows?
- Thread starter bfourman
- Start date
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ScottyBoy
Full Access Member
Also, since you have a 2000, you will need to modify that electric fan harness to be triggered by the AC compressor. You need a relay to convert the positive wire on the compressor to get able to trigger that negative trigger on the harness. The blue trigger wire will be connected to that relay, and the green trigger wire is the temperature trigger and that one will need to be connected to the PCM. I did all this when I installed E-fans on my 2001 Burban with a Blackbear Performance tune. Go check out my install thread that I did, maybe it will help you out. 
http://www.tahoeyukonforum.com/threads/i-installed-e-fans-on-my-2001.28336/
Also, if for some reason you would be driving/towing with the AC off, you could also end up wiring up a manual override switch to basically force both fans to turn on high. When the engine gets up to temp and triggers the fans on, both fans turn on low. But when the engine is up to temp AND the AC compressor is on, then both fans will be running on high. So you can essentially rig up a switch to turn the fans on just like the AC compressor wire will.
http://www.tahoeyukonforum.com/threads/i-installed-e-fans-on-my-2001.28336/
Also, if for some reason you would be driving/towing with the AC off, you could also end up wiring up a manual override switch to basically force both fans to turn on high. When the engine gets up to temp and triggers the fans on, both fans turn on low. But when the engine is up to temp AND the AC compressor is on, then both fans will be running on high. So you can essentially rig up a switch to turn the fans on just like the AC compressor wire will.
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Yeah I am going to go through the harness and strip the headlight/park light stuff that I don’t need.
It helps to be friends with the junkyard owner [emoji3]
Scotty I have read your write up a few times and plan on following it. Nice work!
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It helps to be friends with the junkyard owner [emoji3]
Scotty I have read your write up a few times and plan on following it. Nice work!
Sent from my iPhone using Tapatalk
Started with this mess:
And ended up with this:
Yes that’s the dining room table, my wife went to town for the evening [emoji3]
I seem to be missing the pin to run to the PCM, but there is a small 2 pin weatherpack connector just down the line from the fuse block with a green and blue wire, I suppose either find another JY truck and rob the connector or run my own wires? Pretty sure I can source a PCM pin online.
Blackbear was nice enough to activate the fans with my original tune, so that’s sorted.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
And ended up with this:
Yes that’s the dining room table, my wife went to town for the evening [emoji3]
I seem to be missing the pin to run to the PCM, but there is a small 2 pin weatherpack connector just down the line from the fuse block with a green and blue wire, I suppose either find another JY truck and rob the connector or run my own wires? Pretty sure I can source a PCM pin online.
Blackbear was nice enough to activate the fans with my original tune, so that’s sorted.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
Tonyrodz
Resident Resident
Good thing your wife didn't see that!Started with this mess:
And ended up with this:
Yes that’s the dining room table, my wife went to town for the evening [emoji3]
I seem to be missing the pin to run to the PCM, but there is a small 2 pin weatherpack connector just down the line from the fuse block with a green and blue wire, I suppose either find another JY truck and rob the connector or run my own wires? Pretty sure I can source a PCM pin online.
Blackbear was nice enough to activate the fans with my original tune, so that’s sorted.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
ScottyBoy
Full Access Member
Started with this mess:
And ended up with this:
Yes that’s the dining room table, my wife went to town for the evening [emoji3]
I seem to be missing the pin to run to the PCM, but there is a small 2 pin weatherpack connector just down the line from the fuse block with a green and blue wire, I suppose either find another JY truck and rob the connector or run my own wires? Pretty sure I can source a PCM pin online.
Blackbear was nice enough to activate the fans with my original tune, so that’s sorted.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
If you are missing the section of the harness that goes to the engine computer, you can actually just get a single pin and splice it into your harness. You really only need one because the green wire is the only one that will go to the computer. The blue wire will need to connect with the AC compressor trigger wire, but be sure to use a relay to change the polarity from positive to negative.
You can find a green wire with a PCM pin on just about any LS engine truck. Just unplug the computer and peel the wire loom back and look for a green wire. Then use a small pocket screwdriver or a pic to remove it from the PCM plug.
Finally got a chance to get this done tonight.
Now bear with me for a few more questions. The fans run on low speed at startup, normal? With the A/C the fans kick to high but cycle on/off with the clutch. Normal? From reading my specs from BB I took it to mean the fans would run for a minimum of 90 seconds with the a/c to avoid
constant cycling.
Haven’t driven it yet, tomorrow we will see if I can feel a seat of the pants difference.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
Now bear with me for a few more questions. The fans run on low speed at startup, normal? With the A/C the fans kick to high but cycle on/off with the clutch. Normal? From reading my specs from BB I took it to mean the fans would run for a minimum of 90 seconds with the a/c to avoid
constant cycling.
Haven’t driven it yet, tomorrow we will see if I can feel a seat of the pants difference.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
I have had the Dorman fans and ls1 harness for 4 or 5 years now. No problems from any of it. Parked on a 105* day, towing our boats in the same hot days... I love mine. Mainly for the ice cold a.c. no matter what. But also for the load off the motor.
Quick update on this. So far I really like the efans. Towed the Jeep for a few hours without any issues, truck seemed to have more pep. Ambient temp was in the 40s, so not really a cooling system test.
I did have to replace the OEM high speed relay in the secondary PDC, when it went out it kept the fans from running at all, low or high. Luckily I noticed the engine temp creeping up on the ScanGauge while I was unhooking my trailer at home and was able to troubleshoot before any damage occurred.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
I did have to replace the OEM high speed relay in the secondary PDC, when it went out it kept the fans from running at all, low or high. Luckily I noticed the engine temp creeping up on the ScanGauge while I was unhooking my trailer at home and was able to troubleshoot before any damage occurred.
2000 GMC Yukon XL K2500 6.0/4L80e/3.73s/BlackBear tune
2014 Aerolite 282DBHS TT
bottomline2000
Full Access Member
Just want to confirm..u do not have an issue with the fans being on constantly regardless of temp of a.c. pressure? Meaning they don't cyle on until you are at temp or your a.c. cycles on?
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