my fan relay doesnt work anymore, so i need to wire a toggle switch to the inside of the car so i can turn the radiator fan on/off. i'm new to all the car / wiring stuff, so i need detailed instructions on how to do it. help would be greatly appreciated.

 

Easy. First, determine the polarity of the wires coming off the fan. Ground the negative on the frame, preferably where there is little to no paint, as you want to scratch it off where the wire contacts the frame. Next, run the positive wire for the fan into the passenger compartment along with a hot positive wire off of the battery (don't connect it to the battery until you are finished though). The 12V hot goes to the "power" connector on the toggle switch, then the 12V to the fan goes to the "switched" connector on the switch. It may also have a ground connector for an indicator light, in which case run that to the closest ground point. Mount the toggle switch where it can easilly be reached, but hidden away so it does not look to bad. Its mostly a matter of preference. For getting the wires through the fire wall, you may drill a small hole in the factory wire bushing, then pull the two wires through with a coat hanger or bailing wire. When finished, connect the hot wire to the positive terminal on the battery and call it good. be sure to properly insulate all wires from heat sources which could damage them.

Goood Luck,

 

Um...You really should put a relay in there somewhere or you'll be firing stuff in no time..Power to switched relay then to the fan..Otherwise the fan may not work when you need it most. You must remember most electric fans draw some decent power, which means you really need to use a relay.

 

Q: My relay doesn't work anymore so I'm gonna

a) - Spend 45 minutes figuring out what wires do what
- 30 minutes installing a switch and running wires
- 5 minutes a week jumpstarting your car when you forget to turn the switch off
- and turn the car into the wiring nightmare 80% of the people here complain about when they first get the car
- running hot wires all over the car is a major fire hazard and in a few years will become an untracable electrical gremlin

orrrrrrrrr......

b) - Spend 1 minute disconnecting 1 connector, sliding the old relay off of the bracket, sliding the new $5 relay onto the bracket, and reconnecting the connector, and rest easy knowing the job was done right and not rednecked/band-aided.

 

i would definitely use a relay.

 

"knowing the job was done right and not rednecked/band-aided."

You callin' me a *******? Ah aint no *******...

Yeah, a new relay is the best solution. I by no means suggest this for a permanent fix. And if oyu use it for a very short peroid of time (enough to get to a parts store) you won't need a relay in the wiring. However, if you don't put in a relay in your wiring and use it constantly, you will have problems. Sorry for the ommission,

 

thanks for the replies. i'm still thinking what i should do. i'll tell you the outcome. thanks again

 

I just did that not long ago with the help of a mate.

Here is a drawing of the set-up, The manual switch you can put in place if you want to. This will override the ECM's temperature activation so you can turn it off or on when ever you want to. And if you forget the ECM will turn it at the programmed temperature in the chip.

I would also definitely use a realy and have the ECM connected to it also. If you just had a switch don't forget to get one that has a high AMP rating maybe something around 20amp.

 

Use a 30-50 amp switch, Ive had too many 15 and 20 amp switches burn out on me.

I never connected any switch back to the ecm, I find the computer rather useless in my 84.

 

That way if you run a relay you only need a 6amp switch to turn the fans on because all you do is activate the relay and you don't have almost any current running through the switch.