Hayden Adj Fan Switch
05-26-2003, 04:48 PM
#1
Hayden Adj Fan Switch I recently performed a cooling fan mod that did not work as I expected. I installed a hayden adj fan switch that works in conjunction with a temp sensor. This allows the low speed fans to turn on when my 160 stat opens. No dash switch needed and no extra cables into the interior. The fan mod seemed flawless, except the instructions to wire the fan switch were not feasable. The fan switch cable was connected to a constant power source. This made the fans stay on even after I turned the car off, until the temp reached the shut off point. Eventually this will drain any battery till it dies. So I found an open slot on the lower fuse block called ETC. I dont know what its purpose is, but it only has power the ignition is turned on. So I decided to wire the fan to that slot instead. It works as I expected, no more worries on the battery dying. This mod works great, but only the low speed fans kick on. Does anyone know how to make both high speed fans kick on with the switch I currently have? That would make this mod perfect.
05-27-2003, 04:05 PM
#4
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Re: Hayden Adj Fan Switch What I had planned, before I got the Predator,
was to do something like the fan switch mod but
using a radiator-mounted thermostat. I even
went and bought a couple of Selco 170F, spade-
lug 'stats and potted one up in JB-Weld to make
it more weatherproof. These are pretty cheap and
high-enough current to run the relay coil if not
the fan directly.
Not adjustable like the Hayden, but it doesn't
really have to be - just need a setpoint below
your desired coolant temp by 10F or so.
As far as I've read, all of these fan mods run
the low speed fan only. You should set your high
speed fan in software to kick on about 3-5F above
where you see the thermostat holding temp in
normal driving (3F will let you hear the fans
after a hard run sometimes, 5F usually not).
The high speed fan will be your "backstop",
the thermostat (coolant) will be normally in
control, and the fan switch / radiator-mounted
'stat ensures the tank is cool enough to be useful.
It seems to me like the whole fan scheme could be
reworked with add-on relays to be more sensible
(like with a pair of staggered-temp tank-mounted
thermostats) but there's something about fault
codes from the fans that I don't understand
anything about. But I bet there's a way to fool
them, if done right with relay logic. Anybody have
the inside scoop on this aspect, let me know?
was to do something like the fan switch mod but
using a radiator-mounted thermostat. I even
went and bought a couple of Selco 170F, spade-
lug 'stats and potted one up in JB-Weld to make
it more weatherproof. These are pretty cheap and
high-enough current to run the relay coil if not
the fan directly.
Not adjustable like the Hayden, but it doesn't
really have to be - just need a setpoint below
your desired coolant temp by 10F or so.
As far as I've read, all of these fan mods run
the low speed fan only. You should set your high
speed fan in software to kick on about 3-5F above
where you see the thermostat holding temp in
normal driving (3F will let you hear the fans
after a hard run sometimes, 5F usually not).
The high speed fan will be your "backstop",
the thermostat (coolant) will be normally in
control, and the fan switch / radiator-mounted
'stat ensures the tank is cool enough to be useful.
It seems to me like the whole fan scheme could be
reworked with add-on relays to be more sensible
(like with a pair of staggered-temp tank-mounted
thermostats) but there's something about fault
codes from the fans that I don't understand
anything about. But I bet there's a way to fool
them, if done right with relay logic. Anybody have
the inside scoop on this aspect, let me know?
