Nelson harness not working with 05 Fan swap. Any ideas?
03-19-2010, 12:23 PM
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Nelson harness not working with 05 Fan swap. Any ideas?
Nelson hasn't called me back. So, with the weekend coming up I'm kinda screwed. Here is the deal:
I had the nelson fan harness and the flex-a-lite fans for the past 3 or 4 years. Been working fine, besides the fan motors going out on a regular basis every 1 1/2 years or so. I DO NOT have the pcm controling the fans. I've been manually turning them on and off by a 30 amp switch (running from the blue wire) for low speeds and letting one come on high with the a/c with the green wire hooked up to the a/c.
Last year one of my motors took a dump and one of the relays did too. I called nelson and he told me that they should come on high if I grounded the blue wire and gave power to the green wire. Well only one would. So I ran the green wire to the toggle and grounded the blue wire. I've been turning that one fan off/on high as needed (during the winter).
It craped out and I upgraded to the 05' fans/34" radiator. I ordered the 05 pigtails from nelson's. Hooked everything up the way the harness is supposed to be and nothing would work as far as the toggle is concerned.
One fan does come on high when the a/c is turned on. I thought maybe the other fan wasn't working, but checked it by switching the connections between the fans and each one works fine. I called nelson, he never called me back. So I decided to see if I could rig one fan to come on high with the toggle, as previously mentioned. When I did this (blue grounded/green to toggle), as soon as i hooked up the battery, the fans would both come on low with the toggle off. If I turn the toggle on, both come on high.
How do I get both to come on low with the toggle? Somethings wrong somewhere, just can't figure it out. I do plan on having my tuner tune the pcm for them, just have to find the time to drive 4-5 hours and come up with some more money.
Please post any ideas, help or experiences about this issue. Thanks!
I had the nelson fan harness and the flex-a-lite fans for the past 3 or 4 years. Been working fine, besides the fan motors going out on a regular basis every 1 1/2 years or so. I DO NOT have the pcm controling the fans. I've been manually turning them on and off by a 30 amp switch (running from the blue wire) for low speeds and letting one come on high with the a/c with the green wire hooked up to the a/c.
Last year one of my motors took a dump and one of the relays did too. I called nelson and he told me that they should come on high if I grounded the blue wire and gave power to the green wire. Well only one would. So I ran the green wire to the toggle and grounded the blue wire. I've been turning that one fan off/on high as needed (during the winter).
It craped out and I upgraded to the 05' fans/34" radiator. I ordered the 05 pigtails from nelson's. Hooked everything up the way the harness is supposed to be and nothing would work as far as the toggle is concerned.
One fan does come on high when the a/c is turned on. I thought maybe the other fan wasn't working, but checked it by switching the connections between the fans and each one works fine. I called nelson, he never called me back. So I decided to see if I could rig one fan to come on high with the toggle, as previously mentioned. When I did this (blue grounded/green to toggle), as soon as i hooked up the battery, the fans would both come on low with the toggle off. If I turn the toggle on, both come on high.
How do I get both to come on low with the toggle? Somethings wrong somewhere, just can't figure it out. I do plan on having my tuner tune the pcm for them, just have to find the time to drive 4-5 hours and come up with some more money.
Please post any ideas, help or experiences about this issue. Thanks!
03-19-2010, 12:45 PM
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have you tried checking if theres current flowing to the fan (the one not turning on), you can use that lil pointy thing with the light bulb in the handle i forgot what they are called. that would be your best bet in finding the problem.
somehow somewhere the current is not flowing thats my guess
somehow somewhere the current is not flowing thats my guess
03-19-2010, 12:51 PM
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Both fans on low with toggle would mean "toggle on" provides a ground.
blue needs a ground to turn fans on low.
green needs a +12V to turn one fan on high.
blue grounded and green +12V will turn both on high.
Assuming all relays are working correctly..... I would consider replacing them if you haven't.
03-19-2010, 01:47 PM
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I forgot to add that the only way I can get the fans off is disconnect the battery. Thats with the blue grounded, green to toggle and the toggle in the off position. When I turn the toggle on they both come on high, turn the toggle off they both stay on low until I disconnect the battery. I've checked the relays, do they all have to be 5 pin? I've replaced the outer ones with 4 pin relays and left a 5 pin in the middle. I don't know if this would have made a difference or not, considering the outer relays don't have wire or connection in the middle where the 5th pin would be.
Do I need to run a second switch? How do I do that?
Do I need to run a second switch? How do I do that?
03-19-2010, 02:47 PM
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The fans will always be on with battery power if you permanently connect blue to ground.
Here's what you need to do. Wire the blue to the toggle. Wire the other end of the toggle to your ground connection. Then hook the green wire back to A/C clutch wire in the truck harness.
When you get it tuned, you need to put the pin on the blue wire and run it to the PCM. The PCM will provide your ground.
Here's what you need to do. Wire the blue to the toggle. Wire the other end of the toggle to your ground connection. Then hook the green wire back to A/C clutch wire in the truck harness.
When you get it tuned, you need to put the pin on the blue wire and run it to the PCM. The PCM will provide your ground.
03-19-2010, 03:15 PM
#7
The fans will always be on with battery power if you permanently connect blue to ground.
Here's what you need to do. Wire the blue to the toggle. Wire the other end of the toggle to your ground connection. Then hook the green wire back to A/C clutch wire in the truck harness.
When you get it tuned, you need to put the pin on the blue wire and run it to the PCM. The PCM will provide your ground.
Here's what you need to do. Wire the blue to the toggle. Wire the other end of the toggle to your ground connection. Then hook the green wire back to A/C clutch wire in the truck harness.
When you get it tuned, you need to put the pin on the blue wire and run it to the PCM. The PCM will provide your ground.
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03-19-2010, 08:49 PM
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03-20-2010, 01:24 AM
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Thanks for the info!
Let me get this straight. The toggle has a blue, black, and red wire.
blue = fan harness
black = ground
red = power
The black is already grounded, what exactly do mean by "Wire the other end of the toggle to your ground connection"
Wiring/electrical is my big weakness, so please be patient with me!
Let me get this straight. The toggle has a blue, black, and red wire.
blue = fan harness
black = ground
red = power
The black is already grounded, what exactly do mean by "Wire the other end of the toggle to your ground connection"
Wiring/electrical is my big weakness, so please be patient with me!