Official Electric Fan wiring thread!

[Link]

Well then I will leave it as it is for now, and if the fan is not turning on at the right times I will then change it up some. Does someone know what the stock temp the fan turns on low and then high at? If this does not work I will wire it as the first post says and only utilize high speed.

Thanks!

[bsturman92]

Hey guys been postin in many threads and still finding nothing... My 318is I installed a Volvo fan and wired it to the aux wiring... Worked perfect but would have to hit a/c button... Finally ordered a three prong 80 88 switch from 318ti and now won't work at all.. Weather I hit the switch or not.... Now heres the catch..... The ONLY wait works... I have to completely disconnect the wiring for the fan and unplug my battery,... Re-wire the fan and hit a/c button and it works for literally 5 seconds then shuts off completely and won't work again.... All fuses are totally fine none are blown.... I'm lost as hell and need to get this working... I turned my car on and in plugged both hi speed and lo speed relays and none of them click... Please throw ideas at me cuz I'm over this... Been months now and posted in many threads

[RoadHazard]

What did you have in there before the new radiator switch? Can you put it back and see what will happen?

[bsturman92]

It was my stock switch for my 318is.. and my dumb ass art it outside and left it for two days and it rained.. its all krusty now I don't wanna put it back k in

[Roysneon]

Oh God! I finally wired up a relay and put an e36 318i fan switch in the rad. So awesome to have a car that turns the fan on when it's hot and turn it off when it's cooled down. I pulled all the stock wiring from my parts car (late 325is with a/c) and transplanted it to mine (Euro 318t NO OPTION car). The wiring needs to be cleaned up and ran along the stock harness but it works! I'm pretty proud of myself since a few weeks ago I didn't know how a relay worked and a year ago I couldn't read an ETM.

[328ijunkie]

MEGA UPDATE! See first post. Hope that helps most of the people PMing me and stuff. Hard to get back to everyone on an individual basis.

[Roysneon]

Solid update. I have learned a lot just from reading your posts and derping around with relays and wiring in the past year.

[328ijunkie]

:P Glad i could be of some help! Holler if i can help any more.

[nyChris]

If any thread was worthy of being a sticky, this would be it.

Just got my Spal all wired up. Thanks for the info!

[RockingM]

My first post would be on a fan thread. You know shit hits the fan...

Anyway. Let see if I got some of this right. I'm going to use the stock ac aux fan for cooling and want it to come on at high. I'll need a new switch for the rad. to fan. I'll need to change the wiring at the fan plug. Is that all to start.
I don't want another fan in the engine bay. I gave up on the clutch fan today because it wanted to cross thread and after it was bounced across the shop a few fan blades flew off so it's in the scrap pile. I'm a logger, that's how I roll. ;)

Now, the wiring at the plug I'm not sure about. I want it to just run on high.

And, any other alternatives for fan switches? I'd like to just pick on up at the auto parts store.

Oh yea, I'm also megasquirting the beast tomorrow.

[dsobering47]

I wired in a new fan, that kicks on only when the fan switch closes for the high side, and I have a manual override switch that grounds the fan relay in case I want the fan on. 80*C thermostat with 80/88 fan switch here.

[ArtClassShank]

Just replaced my radiator, and my fan switch. I was having problems where my fan would only kick on with A/C. The fan wires work fine when jumped right before the switch, and the switch is getting plenty hot(confirmed with IR).

My mechanic buddy checked the switch with a multimeter as the car was reaching the warming up milestones, and it wasn't registering any current. He seems to think this is the problem, but I think its air still in the system. He says the only way it could work would be with a 3 prong switch.

I'm not an electrical guy, so hopefully it doesn't come down to wiring, especially since my car was wired by OP.


Forgot to buy connectors today, so I'll have to see if this switch works tomorrow. Hoping I didn't get a bad one.

[ArtClassShank]

It works!

Could have been the fan switch or an air pocket, but high kicks on a tick above middle.

[e30rapidic]

There is a diode underneath the fuse box under the hood. It keeps your a/c compressor from kicking on when your temp switch turns the fan on. It usually doesn't go bad, but if it does, your fan won't run when you click the a/c button.

old bump here...

long story short, snowflake switch doesn't light up and it won't kick the aux fan on. Diode?

Interesting! I'm trying to get my AC working again after may years of not having it. If I press the blue snowflake button, it does not light up. However I took the switch apart and it did light up when I jumped pins 2 and 4. The recirc button lights up and functions as it should.

The aux fan hadn't turned on in years via that switch either so for or the longest time I had the aux fan running through a manual switch since a new thermo switch didn't fix the issue. I rewired everything as it was originally designed and still not getting the aux fan to kick on via the switch. Fan will kick on high and low speeds if I jump it.

I have also disconnected and jumped the pressure switches on the dryer.

***edit - bypassed the the diode and nada. Still no fan or blue illumination***

[Mr Mpower]

hi! wich car i need fo find in the junkyard for a fan to my m52 e30? maybe this answer need to be in the first post!