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DISCUSSION => Electrical => Topic started by: D. Clay on September 24, 2007, 10:24:47 PM

Title: Two speed fan question.
Post by: D. Clay on September 24, 2007, 10:24:47 PM
There are circuits for low and high fan speeds that come from the temp sensor in the radiator. Also a low speed that comes on with the A/C. I heard of using the low speed wire to the resistor to activate a relay for the high speed. It looks like this would turn off the high speed from the radiator if the A/C wasn't on. I'm not real sharp on wiring and reading diagrams.
How would you wire the system to have the fan on high speed with the A/C also preserve the low and high speed circuits from the radiator sensors.
Title: Two speed fan question.
Post by: FL318is on September 24, 2007, 10:41:17 PM
Thanks for the diagram.  I am still trying to troubleshoot my a/c.  I "jumped" the compressor from the fuse box and it kicked in and was cool.  So I think there must be a relay problem somewhere.  I am hoping to see it on this diagram.
Title: Two speed fan question.
Post by: D. Clay on September 25, 2007, 03:55:21 PM
Anyone? A wiring diagram is attached.
Title: Two speed fan question.
Post by: a.12912 on September 25, 2007, 05:28:51 PM
I'm under the assumption you'r at a similar stage of a same project to my self. the project is removing the engine viscose fan , clutch and replacing it with a draw / pull electric fan. the scenario that I've come up with is what sensor can i borrow a pick up switch (on/of)  from. alternatively I've placed consideration into an electronically controlled hiestes electrical voltage based switch . the switch will utilize the signal from the the temp sensor for the dash gage and be adjusted to turn on /  of were required.

though I'm aware of the temp switch on the side of the radiator  , then why not use it . the switching temp is also of concern, sounds a little to high? is there such a three stage temp switch from a later moder such as e36? the two stages for the air con condenser fan and separate for the radiator electric fan?

which radiator fans / sources and brands are being successfully used ? size?

cheers all
Title: Two speed fan question.
Post by: D. Clay on September 26, 2007, 10:50:07 PM
a.12912
I sent you a PM.