Oil cooler fan switch
04-28-2009, 11:35 AM
#16
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I think I'm missing something here. If a wire is cut and a switch spliced in it seems like SOMETHING is going to not work unless the switch is on. Does the fan still run at both high and low speeds when the switch is off? Unless I am misunderstanding how this is wired I'm guessing one speed or the other is now dependant on the switch.
). When the switch you've added is passing continuity (for our purposes here, let's say "off"), the circuit to the temp switch is closed and the auto temp switch functions exactly as if there were nothing in line. So if you were to forget to hit your add-on switch, all works as designed. Hitting the switch to "on" interrupts the circuit, which is tantamount to what the temp switch does behind the headlight: i.e. opening the circuit, tripping the high-speed fan function. Experiment yourself by pulling the plug out of the socket: your fan will run at high speed (circuit is open) until you plug it back in (closing the circuit). It works perfectly fine.FWIW, this is what I did years ago, albeit I felt uncomfortable running unfused high current all the way back to the dash to my switch, so I wired a relay so my switch is fed by a very low-current tapped from within the dash, and the relayed interruption to the oil-temp switch is right at the switch, minimizing the run of high-current wire. But after I had done this (again, many years ago), someone much smarter than I am (which is not hard, mind you) figured out that two wires tapped off the CCU (climate control unit, right under the dash), will do the same thing. Doh ...easy! If I were one comtemplating a manual switch, I would do it this way ...a hem, Mike, you listening
Someone here can perhaps post which wires those are.
Edward
04-28-2009, 12:45 PM
#17
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Very well said Ed... I looked into doing the CCU way and this was a much better way to do it for me...Thanks for clarifying how it works.. I knew it worked but I had a tough time explaining it...
04-28-2009, 01:31 PM
#18
Barney,
I see you do not have fog lights, non do I.
What I did (not thats it is easier or less expensive) was to use the fog light switch to activate a normally closed relay contact in the oil cooler temperature switch wire. I located the relay at the oil cooler and only had to rewire in the right fenderwell to cut in the relay contact and use the fog light power wire to activate the relay.
I changed the insert in the fog light switch to a defroster insert mounted vertically (looks like a radiator).
So with the running lights on, when I pull out the oil cooler fan switch it lights up an d the fan runs. With the switch off the cooler fan works normally.
Mike
I see you do not have fog lights, non do I.
What I did (not thats it is easier or less expensive) was to use the fog light switch to activate a normally closed relay contact in the oil cooler temperature switch wire. I located the relay at the oil cooler and only had to rewire in the right fenderwell to cut in the relay contact and use the fog light power wire to activate the relay.
I changed the insert in the fog light switch to a defroster insert mounted vertically (looks like a radiator).
So with the running lights on, when I pull out the oil cooler fan switch it lights up an d the fan runs. With the switch off the cooler fan works normally.
Mike
04-28-2009, 03:33 PM
#20
Three Wheelin'
When the switch you've added is passing continuity (for our purposes here, let's say "off"), the circuit to the temp switch is closed and the auto temp switch functions exactly as if there were nothing in line.
