I installed a manual fan switch in my car. (I made the switch myself) When I cranked the car with the switch off both fans started running. So, I disconnected the switch, thinking I most have did something wrong. With the switch disconnectted both fans still come on as soon as I crank the engine. Any ideas?

 

How did you wire up the switch? An explanation of what went where would help a lot.

 

you probably mixed up some wires somewhere along the line...go back and double check everything. Might of mixed up how the wires connect to the switch too

 

There are several different ways to do a fan switch. You need to tell what method you used and what you did.

 

I used this one http://users.oco.net/xero/fanmod/ and compared it with Shoebox's. I checked it when I first hooked it up. With the car swithed on and not running the fans worked correctly. When I noticed the fans coming on when the car was first cranked up I disconnected the two wires that splice into the fan wires under the hood near the computer. Also I used a switched power supply for the led's.