Fan switch keeps frying

[JerzyIroc]

i wired both fans to a switch a few weeks ago. the first time i did it with 14 guage wire. the switch would get real hot real quick eventually frying the switch. it happened to 3 switches. finally i rewired it with 12 guage wire and it seemed fine til today when i almost got into an accident from the smoke of burning wires. what the hell is going wrong? i know it's wired right. do i need a higher amp switch? is wiring both fans to one switch too much? too many amps?

[91DropTop]

you should be running the switch to a relay and the relay to the fans, the fans pull too many amps for a switch alone esp dual fans....your not at federated anymore:rofl:

[BonzoHansen]

Search this forum, there are a bunch of wiring diagrams posted. Get a real fan switch & some relays.

[bubba428]

sounds to me like you have the switch on the hot wire(+) you need it to be on the ground.

[BonzoHansen]

sounds to me like you have the switch on the hot wire(+) you need it to be on the ground.

It's still all part of the circuit. He's not using realys, positive of negative is meaningless for his issue.

[91DropTop]

sounds to me like you have the switch on the hot wire(+) you need it to be on the ground.

either way your still gonna pull too much amperage for a switch esp that he has dual fans on 1 switch

[bubba428]

It's still all part of the circuit. He's not using realys, positive of negative is meaningless for his issue.

depends on how its wired....it sounds like its a hot wire set up...meaning the wires go strait to the battery. If its run though a ground and he gets a higher tolerance switch there won't be an issue

[deadtrend1]

depends on how its wired....it sounds like its a hot wire set up...meaning the wires go strait to the battery. If its run though a ground and he gets a higher tolerance switch there won't be an issue

He needs to run relays, which are designed for this purpose. Hes pulling too much current through the switch.

Weather he has a hot wire set up, cold wire setup whatever you want to call it.

[JerzyIroc]

i'm runnun power from the bat to the switch. the two power wires from the fans to the switch. ground the switch to under the dash. and the fans are grounded to the chassis

[91DropTop]

i'm runnun power from the bat to the switch. the two power wires from the fans to the switch. ground the switch to under the dash. and the fans are grounded to the chassis

your lucky your cars not on fire...haha jk but seriously we gotta get you a relay setup.


run b+ to the 30 on the relay preferably fused or breaker or something
run switched power to 85
run ground to 86
and run power to fan from the the Normally Open (i think 87a)
i would put relay on the firewall somewhere

[bubba428]

I have mine set up like that and it didn't fry my switch yet?

[JerzyIroc]

lmao thanks.. ya i gotta do a relay setup. argh.

[JerzyIroc]

you have both fans wired?

[BonzoHansen]

I'd run one relay per fan, or a total of 3 if you want to get fancy.

[BonzoHansen]

http://www.njfboa.org/forums/showthread.php?t=17456&highlight=relay

among others...

[91DropTop]

I'd run one relay per fan, or a total of 3 if you want to get fancy.

fancy would be getting a new temp switch in the block and having that control the relay instead of a dash switch, like stock...what a concept hahaha

[JerzyIroc]

fancy would be getting a new temp switch in the block and having that control the relay instead of a dash switch, like stock...what a concept hahaha

HA. **** fancy. i barely wanna wipe my ass when i **** because its too much work lol. jk. nah im fine just putting it to a switch. So if i were to use two relays im guessing id have to use two switches?

[johnjzjz]

you could use one switch and set both to ground through one switch << also a 5 amp plastic rocker is not the kind of switch everyone is talking about < you will need a real metal type 10 or even 20 amp type Jegs sells or an old type hardwear store will have you can run two 30 amp fans from a 10 amp metal switch by using the ground on the relays as the driver in that way all the load is on the relay not the switch -- jz

[WildBillyT]

If you get a two pole relay you can get away with just using one, but you definetly should not be running high amp accessories like fans without a relay.

[JerzyIroc]

wait so if i use one switch but two relays im gonna splice wires going from the relay to the switch together? and just ground each relay out? im way off arent i lol

[BonzoHansen]

Yes, 1 switch is all that is needed. You can split the trigger circuit to each relay.

Now is the time to get a real fan switch and not a toggle. You can keep the toggle for back up if you like.

[JerzyIroc]

wow. thats awesome man. you guys rock

[BonzoHansen]

Summit sells simple kits with a fan switch and one relay, you can get a 2nd relay in a local parts store. Do you have AC? You have to splice that into the circuit too.

[91DropTop]

check this out for future needs...every schematic for 3rd gens known to man


http://www.austinthirdgen.org/index.php?pid=19

[JerzyIroc]

ok so i know a lot of you guys are gonna be like wtf since this post is about 3 months old buutt... i finally got around to doing the switch a few weeks ago. (yes it took me that long to get time) and im not gettin it. i have bat going to 30, the fan going to 87, the switch going to 85, and ground going to 86. nothing. still wont work. WTF?! its a brand new relay and switch too..

[sweetbmxrider]

does the fan work?

[JerzyIroc]

ya i just put the wire from the fan right to the battery.

[sweetbmxrider]

hmmm...where is it grounded? do you here the relay switch? i am assuming no. is the power wire fused? blown? got a test light :lol: it would help see whats where and whats missing!

[JerzyIroc]

its grounded to the chassis. didnt hear the relay click. and fuse isnt blown.

[sweetbmxrider]

well if you have a test light, check to be sure the ground and power are good.

[sweetbmxrider]

wait, read the schematic. you aren't supposed to ground 86. you put it to a hot lead. either always hot or hot in run! there's your problem

[BonzoHansen]

This might help.
http://img.photobucket.com/albums/v359/SIBLY/Cars/1098relay.jpg

[JerzyIroc]

sweeet. i gotta buy you guys a cake or something... soo just get a two pin toggle switch?

[BonzoHansen]

Yes, a simple toggle can be used. As can a factory style fan switch. Or both. And an AC lead (assuming it grounds). I like automated fans because I forget stuff, lol. I would personally used high & low temp triggers for dual fans, but this will work well if a single trigger is to be used. On the dual setup each fan has its own power lead so if there is a failure (blown breaker/link) the other still works.

If you decide to use links a 10g power lead should be protected by a 14g link. Breakers can be also used. Fuses don’t always work well because they don’t like the initial voltage spike when the fans come on. Just my experience.

[JerzyIroc]

i dont have an ac so i can just run it to the switch i guess. i am so pathetic. am i the only one that can work on anything with little to no problems but when it comes to working on your own stuff you suddenly become an idiot?

[sweetbmxrider]

happens to the best of us...

[JerzyIroc]

lol its so annoying. ive worked on everything from fire trucks to motorcycles with no problem. for the life of me when it comes to working on my car im on dee dee dee mode. i used to wire things out the arse when i was a fire truck mechanic but i cant even do a simple damn toggle switch relay set up for a fan... wtf??? thank god im not a pot head. id really be screwed.

[BonzoHansen]

You can eliminate the fan switch, the toggle switch and/or the AC switch. You just need one of them. Notice they are spliced into the same circuit. That is the ‘trigger circuit’.