# Wiring electric radiator fan with toggle **URL:** \ **Category:** Shift518 Automotive\ **Created:** [March 20, 2010, 6:12pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999 "2010-03-20T18:12:03Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 6:12pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/1 "2010-03-20T18:12:03Z")
I want to control my radiator fan with a toggle switch. I want to bypass any temp. sensors and when the switch is on, so is the fan - no exceptions. I know this is simple, but want to hear advice from someone who knows for sure since wiring has been always something I look for second opinions on. Do I need any sort of relay? Won’t the fan draw too many amps without some relay/fuse connection? Can the fan be wired to the switch and the switch to the battery? Any help is appreciated ---
**Author:** ![TurboTravis](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/turbotravis/32/6406_2.png) [@TurboTravis](https://forums.speedlife.net/u/TurboTravis)\ **Post date:** [March 20, 2010, 6:21pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/2 "2010-03-20T18:21:46Z")
> [@Who here still plays.....](https://forums.speedlife.net/t/who-here-still-plays/30216/4): > > I want to control my radiator fan with a toggle switch. I want to bypass any temp. sensors and when the switch is on, so is the fan - no exceptions. > > I know this is simple, but want to hear advice from someone who knows for sure since wiring has been always something I look for second opinions on. Do I need any sort of relay? Won’t the fan draw too many amps without some relay/fuse connection? > > Can the fan be wired to the switch and the switch to the battery? > > Any help is appreciated Couple different ways to do it, all easy though. Relay may or may not be needed. ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 6:25pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/3 "2010-03-20T18:25:28Z")
> [@TurboTravis"](#): > > Couple different ways to do it, all easy though. Relay may or may not be needed. If you have a minute - post up what you’d do to make it happen I’m trying to get this done early tomorrow morning if possible :thumb ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 6:27pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/4 "2010-03-20T18:27:02Z")
Use a relay. Just a simple 4 pin 30amp will be plenty. Connect 85 to ground, 86 to the toggle (other side toggle to fused 12v+), 87 to the battery through a fuse, and 30 to the fan power wire. Then just ground the fan. this will allow you to run a small wire through the firewall which will make life much easier. ---
**Author:** ![TurboTravis](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/turbotravis/32/6406_2.png) [@TurboTravis](https://forums.speedlife.net/u/TurboTravis)\ **Post date:** [March 20, 2010, 6:29pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/5 "2010-03-20T18:29:04Z")
> [@Thursday in the Square](https://forums.speedlife.net/t/thursday-in-the-square/30171/23): > > If you have a minute - post up what you’d do to make it happen > I’m trying to get this done early tomorrow morning if possible :thumb I don’t know your particular cars wiring, but you could either attempt to trigger your factory relay with a signal that you switch from the cabin, or you could add your own relay and go about it that way. Probably easier to just add your own relay if I had to guess. ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 6:30pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/6 "2010-03-20T18:30:53Z")
> [@Post funny pics of Skunk v1.0](https://forums.speedlife.net/t/post-funny-pics-of-skunk-v1-0/30051/51): > > Use a relay. Just a simple 4 pin 30amp will be plenty. Connect 85 to ground, 86 to the toggle, 87 to the battery through a switch, and 30 to the fan power wire. Then just ground the fan. this will allow you to run a small wire through the firewall which will make life much easier. Please dumb this down for me a bit. What is 85, 86, etc mean? Also - my battery is under my rear passenger seat (a good 10ft from the fan :)) ---
**Author:** ![TurboTravis](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/turbotravis/32/6406_2.png) [@TurboTravis](https://forums.speedlife.net/u/TurboTravis)\ **Post date:** [March 20, 2010, 6:32pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/7 "2010-03-20T18:32:23Z")
> [@FS: 99 Honda Civic DX](https://forums.speedlife.net/t/fs-99-honda-civic-dx/30101/13): > > Please dumb this down for me a bit. What is 85, 86, etc mean? Also - my battery is under my rear passenger seat (a good 10ft from the fan :)) Those numbers are on the relay contacts. No need to go directly to the battery, several sources should be available under the hood, stater solenoid for one. ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 6:41pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/8 "2010-03-20T18:41:12Z")
You have to be careful where you pull power from if you are just going to tag something b/c fans can draw a lot of power. If you pull power from something that isnt designed for that much draw, you can end up either popping a fuse or doing further damage. I would def. make sure it is a circuit that can handle the power draw (starter solenoid would work best). ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 6:42pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/9 "2010-03-20T18:42:58Z")
With the battery being under the seat, triggering the factory relay may be the best option. You would have to use a digital multi-meter to determine whether is is + triggered or - triggered. then simply run power/ground through your switch and then to the relay. ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 6:45pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/10 "2010-03-20T18:45:28Z")
Not sure where you are located, but if you would like help and can bring the car to me I can give you a hand tomorrow morning. However I have to be out of the house by around 9:30 so you’d have to be here around 8/8:30. I live right at the watervliet/latham border. If this is something you wanna do, let me know. ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 6:47pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/11 "2010-03-20T18:47:00Z")
Ok guys - following so far. So how should I have the wiring set up from the fan? What gauge wire do I need? Ill be going to Advance or similar autoparts store. Sorry you need to explain so literally - this is clearly my weakest subject ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 6:49pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/12 "2010-03-20T18:49:37Z")
> [@offroadzj"](#): > > Not sure where you are located, but if you would like help and can bring the car to me I can give you a hand tomorrow morning. However I have to be out of the house by around 9:30 so you’d have to be here around 8/8:30. I live right at the watervliet/latham border. If this is something you wanna do, let me know. I really appreciate the offer - the time restraint isnt going to work for me unfortunately. If you would have any time later in the day or something PM me details. If not Ill give it a try with what info I can get in this thread. +rep ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 7:00pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/13 "2010-03-20T19:00:51Z")
I will be back home around 1ish but the race is on and although I may be a nice guy, I dont do shit when the race is on… lol. If you can wait til later in the afternoon/evening (probably around 5 or 6 or so) you are more than welcome to stop over and I’ll see what I can do. ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 7:04pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/14 "2010-03-20T19:04:05Z")
> [@SKYCUDA](https://forums.speedlife.net/t/skycuda/30215/6): > > I will be back home around 1ish but the race is on and although I may be a nice guy, I dont do shit when the race is on… lol. If you can wait til later in the afternoon/evening (probably around 5 or 6 or so) you are more than welcome to stop over and I’ll see what I can do. More than understandable - Ill pm you if I cant figure it out. If anyone has any advice on this situation please post ---
**Author:** ![TurboTravis](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/turbotravis/32/6406_2.png) [@TurboTravis](https://forums.speedlife.net/u/TurboTravis)\ **Post date:** [March 20, 2010, 7:06pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/15 "2010-03-20T19:06:50Z")
> [@Replaced the battery, now starter just clicks?](https://forums.speedlife.net/t/replaced-the-battery-now-starter-just-clicks/30175/13): > > More than understandable - Ill pm you if I cant figure it out. > > If anyone has any advice on this situation please post Match the gauge of the factory fan wiring on the relay you are adding on (or go bigger, numerically lower), and you can use 16/18 gauge to trigger the relay. ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 7:07pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/16 "2010-03-20T19:07:58Z")
my guess is that the fan will probably be 12 gauge. ---
**Author:** ![offroadzj](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/offroadzj/32/6428_2.png) [@offroadzj](https://forums.speedlife.net/u/offroadzj)\ **Post date:** [March 20, 2010, 7:08pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/17 "2010-03-20T19:08:42Z")
and please do me a favor and find a way through the firewall (rubber grommet, factory wire boot, etc) dont run it through the door jam… you are just asking for a short if you do. ---
**Author:** ![imported\_ST4TUS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_st4tus/32/6290_2.png) [@imported\_ST4TUS](https://forums.speedlife.net/u/imported_ST4TUS)\ **Post date:** [March 20, 2010, 7:20pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/18 "2010-03-20T19:20:50Z")
> [@High speed internet question](https://forums.speedlife.net/t/high-speed-internet-question/30214/26): > > and please do me a favor and find a way through the firewall (rubber grommet, factory wire boot, etc) dont run it through the door jam… you are just asking for a short if you do. Haha I would never wire through the jamb - thanks for your help man, really helped out ---
**Author:** ![ninety1two40](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ninety1two40/32/6332_2.png) [@ninety1two40](https://forums.speedlife.net/u/ninety1two40)\ **Post date:** [March 20, 2010, 8:50pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/19 "2010-03-20T20:50:30Z")
Get a SPDT switch. Center connection from the switch goes to the fan relay signal input. Other switch connection goes to the fan relay signal coming from the ECU (you have to cut the wire from the ECU to the relay). The last switch connection goes to either ground or 12V (depends on relay configuration). That way the switch will either turn the fan on or switch back to auto control from the ECU. ---
**Author:** ![Boxersix](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/boxersix/32/6327_2.png) [@Boxersix](https://forums.speedlife.net/u/Boxersix)\ **Post date:** [March 20, 2010, 8:57pm UTC](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999/20 "2010-03-20T20:57:10Z")
> [@5.31.07 TITS](https://forums.speedlife.net/t/5-31-07-tits/30133/16): > > Get a SPDT switch. Center connection from the switch goes to the fan relay signal input. Other switch connection goes to the fan relay signal coming from the ECU (you have to cut the wire from the ECU to the relay). The last switch connection goes to either ground or 12V (depends on relay configuration). > > That way the switch will either turn the fan on or switch back to auto control from the ECU. ^ This because the first time you forget to flip the switch and leave your car running for 20 minutes while chatting it up with friends you’ll wish you never fucked with it. Tis why my fan on the EG33 WRX is wired key on through a relay. Comes on and stays on as soon as I turn the key. ask me how I know :wierd [Next page](https://forums.speedlife.net/t/wiring-electric-radiator-fan-with-toggle/250999.md?page=2)