Head scratcher...Tune "Fan 2" for A/C only?
09-23-2008, 05:04 PM
#42
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I'm confident I can get the A/C to function how I want, I'll just set it up as a stand alone system.
What I'm really after now is getting the dual speed function on the 18" fan.
Here's what I'm trying to do.
-engine is cold, 18" fan is off
-truck is going more than 55mph, 18" fan is off provided engine is cold
-engine is warm, 18" fan turns on LOW, off after engine cools
-engine continues to warm and is now hot on LOW fan speed, then 18" fan turns on HIGH
Basically all you want is your fans to come on LOW at ~200 and off at ~199 (if you have a stock stat?). Then you can make it come on HIGH if it gets up to 205? and off if it gets back below 204?
I see now that in order to run 1/2 speed I need 1/2 the volts, so the question then is, how do I cut the volts in half when only running a single fan? The A/C fan is out of the picture for radiator cooling. It's not even on the radiator.
What I'm really after now is getting the dual speed function on the 18" fan.
Here's what I'm trying to do.
-engine is cold, 18" fan is off
-truck is going more than 55mph, 18" fan is off provided engine is cold
-engine is warm, 18" fan turns on LOW, off after engine cools
-engine continues to warm and is now hot on LOW fan speed, then 18" fan turns on HIGH
Basically all you want is your fans to come on LOW at ~200 and off at ~199 (if you have a stock stat?). Then you can make it come on HIGH if it gets up to 205? and off if it gets back below 204?
I see now that in order to run 1/2 speed I need 1/2 the volts, so the question then is, how do I cut the volts in half when only running a single fan? The A/C fan is out of the picture for radiator cooling. It's not even on the radiator.
Im lookin for a small transformer or something to get you from 12 volt to 6 volt for a LOW.. then when you command HIGH it trips off your LOW relay and HIGH relay on..
Your goin to need 2 Relays for this to work.
09-23-2008, 05:15 PM
#43
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Pin 30 Goes to your battery with a fuse
Pin 87 To the fan, ground the other wire on the fan
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM..
You can swap PIN 85 and 86, it doesnt matter.
Now im just guessing this right now.. but since you have 3 wires from the fan.
2 Relays are needed
Relay 1:
Pin 30 Goes to battery with a fuse
Pin 87 connect to yellow wire (low?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan #1
Relay 2:
Pin 30 Goes to battery with a fuse
Pin 87 To the Red wire from the fan(high?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan#2
Ground the black wire from the fan..
For your AC Fan
Pin 30 Goes to battery with a fuse
Pin 87 To the fan, ground the other wire on the fan
Pin 85 Ground this pin
Pin 86 Goes to the AC Compressor clutch wire.. ..
Pin 87 To the fan, ground the other wire on the fan
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM..
You can swap PIN 85 and 86, it doesnt matter.
Now im just guessing this right now.. but since you have 3 wires from the fan.
2 Relays are needed
Relay 1:
Pin 30 Goes to battery with a fuse
Pin 87 connect to yellow wire (low?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan #1
Relay 2:
Pin 30 Goes to battery with a fuse
Pin 87 To the Red wire from the fan(high?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan#2
Ground the black wire from the fan..
For your AC Fan
Pin 30 Goes to battery with a fuse
Pin 87 To the fan, ground the other wire on the fan
Pin 85 Ground this pin
Pin 86 Goes to the AC Compressor clutch wire.. ..
09-23-2008, 05:15 PM
#44
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You don't need to buy a dvom, it would just make it easier...
Just test the three wires with a battery and see what you get.
09-23-2008, 05:18 PM
#45
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Pin 30 Goes to your battery with a fuse
Pin 87 To the fan, ground the other wire on the fan
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM..
You can swap PIN 85 and 86, it doesnt matter.
Now im just guessing this right now.. but since you have 3 wires from the fan.
2 Relays are needed
Relay 1:
Pin 30 Goes to battery with a fuse
Pin 87 connect to yellow wire (low?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan #1
Relay 2:
Pin 30 Goes to battery with a fuse
Pin 87 To the Red wire from the fan(high?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan#2
Ground the black wire from the fan..
Pin 87 To the fan, ground the other wire on the fan
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM..
You can swap PIN 85 and 86, it doesnt matter.
Now im just guessing this right now.. but since you have 3 wires from the fan.
2 Relays are needed
Relay 1:
Pin 30 Goes to battery with a fuse
Pin 87 connect to yellow wire (low?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan #1
Relay 2:
Pin 30 Goes to battery with a fuse
Pin 87 To the Red wire from the fan(high?)
Pin 85 You can jump this to Pin 30 or to the battery.
Pin 86 Goes to the PCM for Fan#2
Ground the black wire from the fan..
09-23-2008, 05:20 PM
#46
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Basically i have mine set up like the Fbodys..
09-23-2008, 05:36 PM
#49
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Ya see I don't think us HPTuner users can control the second fan settings nor have a pin to run it... I've check and found no other pins that wound provid a good ground when I manually turned on the "second" fan... Again this is for hptuner users only,...
09-23-2008, 05:39 PM
#50
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Ah, cool. The only thing i'd be worried about with your setup is that I never trust anything that drops voltage like rheostat's and resistors. They never seem to have much life and I know how important reliability can be on a trail truck. I really admire your idea's here though.