Just did a pretty intense search on running a manual fan switch and on every post I saw shoebox respond to them....so your going to love this post ....sorry.

I'm looking to run 2 seperate switches for high speed and low speed. I want low speed to be on one switch with an LED, and high speed to be on a seperate switch along with another LED. There has to be a write up on that somewhere, but all the ones shoebox posted, the links did not work anymore.

Can anyone give me some insight please?

 

Good question!...this is what I'm thinking yet I am not positive so. Shoebox will set it straight when he reads this but here goes... Branch the ground wire to each seperate on/off toggle switch instead of going to just one DPDT switch, then run the low speed (green relay control wire) to one switch and the high speed (blue relay control wire) to the other switch...done! (well done unless your wiring your switch to be always constantly hot then you need the 1-3 amp diodes & resistors for LEDS of course if you want those)

it's the same approach for OBD2 as far as wiring the seperate switches instead of a DPDT center off switch, the diagrams on shoebox's site are a great help of course. I just looked at the his diagrams and it looks like he even upgraded them...nice!

 

i fiured it out last night! i took shoeboxs diagram and then "pretended" that the dtdp switch was two seperate switches

i'm not sure if I'm throwing a code or not with out putting resistors in??? the service engine sson light is on but then again, i have no rear O2s in yet, not sure if remving airbag throws ses code or not...but is it throwing a code while hooking them up like this without the resistors in place??

 

Want to do this mod already but all this reading about resistors and ground wires make me nervous...I am no BENJAMIN FRANKLIN and I cant even tell on a car battery wether black is ground or power....
anyone know a quote for having this installed or do you think i can really do this myself ...

 

Wiring and electircal is so easy. It seems like its rocket science but its not. Have some confidence! You can do this! Just make sure you know what you have to do before getting started. Besides, this is how you learn.

 

just go to autozone and pick up two switches that have lights in them. i did and they work fine.

 

I was going to suggest that you look at it like the switch was split down the center. One note: you must have the low speed switch ON when you turn the high speed switch ON to run both fans at high speed. If you only throw the high speed fan switch, only the high speed fan will run and it will run at high speed. Both fans should run at low speed when the low speed switch is thrown.

The resistors are there to keep OBD-II from thinking there is a problem with the fan circuits. OBD-I does not seem to care much. P1641/P1642 are the codes you will get if the PCM complains about the fan relay control circuits.

You peeps must have a thing for switches. I find it easier just to reprogram the PCM for the fans to come on when I want them to. That way, they never "forget" to come on. Obviously, if you want manual control, you must have switches.

 

I'm just afraid I wont do it right and at start up I burn up a couple of things in the car. The way BADCO described it makes it seem really easy and i can do that but i know there is a lot more than that. I dont even know what a resistor is and if i find out what it is i wouldnt know where to put it

 

You can look at the manual fan switch wiring diagram for OBD-I (what you have on a 1994) on my Tech Page. Depending on how you hook it up, you might not even need any resistors.

I actually don't have any fan switches on my car, but do have two LEDs to tell me when the fans are on.

 

I have the switch and LEDS, I never use the switch, I have the 160 thermostat without tuning and the needle never raises higher than 1/3 above the dead cold mark and the first hatch mark (well I have used the switch one time in 6 mnths when it did get to halfway on the gauge once when I was adusting tire pressure and got to talking to a friend I ran into at a fuel stop)

on a side note: Shoebox I have a LED light come on when I run the heater/ defrost for a while, this is the same light(FAN) that comes on when I run the AC..is this normal? (I have only heard it mentioned coming on with AC) also this light takes a while to even come on sometime after turning AC or heater/defrost on and off and the light takes a while to go off after turning those off as well....hope that wasnt a thread hijack...

 

The low speed fans will come with the a/c system. That includes defrost and bi-level. The fans are programmed to go off 30 seconds after any of those modes are turned off (and the engine temp is lower than the fan ON threshold).

 

hey shoebox, yes that is what i meant by "two switches", just split the diagram right down the middle. And yes the low speed needs to be on and then you throw the high speed fan. thank you for your VERY useful diagrams and everything on your website. Thats more useful than the chiltons or haynes...whatever everyone has. I've been taking a few of my own pictures and installs over the past couple of years. Most of it is body work, my favortie of course! And the other half is all motor work...little bit of electrical here and there.

I have my fans reprogramed and all that jive (160*t-stat). I like switches for multiple reasons. I just got in my VFN dash the other day so I've been having a field day with toggle switches with safety covers! I have one for the csi pump, low fan, high fan, nitrous arm, bottle heater, i forget the rest I want to tie in the parking lights, foglights and headlights with switches as well just to make it look cleaner and it'll be easier to install toggle switches instead of mounting the stock headlight/foglight/dimmer selectors.

Right now I'm having a field day picking out all my gauges for the new dash as well. Speedo gauges are pretty darn exspensive so I dont see me getting one for a week or two

Boobster: We'll help you out with you install step by step if you need that much help. I think its even easier with an OBDI car because all you have to do is ground out the relay under the hood in that fusebox and not worry about ANYTHING else.

 

Thanks A lot for insight and help...its extremely appreciated...this is one mod i have been always wanting to do because the stop and go traffic makes my temp rise high and eventhough the fans come on when they are supposed to Id rather have them come on when i want them to....
I go through SHoebox Website and read it a couple times and then figure out what tools and materials i will need ...
THanks A lot!

 

Shoebox what is your bet suggestion to keep both fans running after you turn the car off? I want to use a thermo switch with a probe on the radiator

 

Tie the output of the thermo switch to a relay that can supply a ground to both fan relay wires.

I know that some cars have this from the factory, but I don't really see the point. Unless you have an electric water pump to also circulate the coolant, the engine is not going to get any cooler.