Thread: Question on wiring fans to a manual switch?

I need to wire my fans so that I can turn them on with a manual switch.

My fan controller in my ECU is dead so they dont turn on at all right now. Need to wire in a switch to control them for the time being til my new ECU comes in.

Anyone got a howto on that by chance? Thanks!

I'm thinking about something similar to being like this:

You don't need the ECU at all, just go + to one lead, - from the other through a fuse and switch. Or, don't even bother with the switch. I relayed mine to the fuel pump so they are always on with car.

Keeps it cool and I never have to worry about the fan not working!

If you do go with a switch though, take it from me and use a RELAY to activate them and use low current wires to the switch. Otherwise, you have a good chance of ruining a perfectly nice switch (can you guess I melted two of them before using a relay? )

Can you draw up what you mean by that? I am not really familiar with how relays work. Thanks!

Check the ECU pin out guide for the fan leads. Run a switch from those leads to ground, that's all you need to do. There is no reason for relays or fuses because they are already used from the factory.

I wired mine up to my AC switch. ymmv

Ok. Let me ask you this, are you suggesting that I cut and run the wire off that or should I use something like a vampire tap for now as the new ECU should fix this.

I personally don't like running fans at all times, seems like it will make them die a premature death. Plus in the winter it will make for some very long starting times haha...

I would prefer having them on say at 200*F and then when ever I see that the temperatures are starting to creep up, kick on the fan and then turn it off. Like if your hitting bumper to bumper traffic etc...

Well, thats the goal. But to accomplish the goal I almost need a wiring schematic. I'm not sure the best way to go about this to be honest. Which is why I'm coming to the forums here for a bit of help Can't do much outside of ask what to do while I am here at work. Thanks for the help!

On my topaz (yah yah...) I used a standard buss lighted switch- worked for years until the wife's friend totalled it.

positive lead from fans to it, negative direct to battery, fuse in between, and done.