What's up guys I have a 91 trans am with a 350 tpi. When I got the car the fans use to come on when I got the car. It was set up with a relationship switch I'm assuming cause the original fan relay was burnt up from what I saw. The fans stopped coming on so I had to run a toggle switch. But I would like them to come on automatic again. Any help on how I would go about wiring it up.

 

Best thing to do would be to get a new (or at least, other) relay just like the factory one, fix whatever is burned up, and put it back like it came from the factory. Which, once some PO with a pr of dykes has got in there and left his p***** tracks all over the place with em, can be IMPOSSIBLE for us out here to even GUESS what all he effed up. You'll just have to trace all the wires and find what he sodomized, and un-eff it up. Rip out whatever GARBAGE he put in while you're at it.

We need a smily on this site like they have on some other sites... a Jeffrey Dahmer saw, to visually indicate "hack".

 

Here's one of the articles in the How-Tos section that may help clear some things up. Lots of good stuff in there you might check it out.
Happy hunting!
https://www.thirdgen.org/electric_co..._spec_mod_dual

 

Well I got out to take some pics. I think this relay is the cooling fan relay it's burned inside. I got a pic of the wires the po cut into its an orange wire a black and pink one a ground and a thin grey one.








That is the relay he replaced with the original one i assume. The sensor on the passenger side is cancelled. I only found one on the driver side. It's a green with white striped wire

 

What I also noticed when they messed up. Is that the ac would not even turn on the fans when the ac was on? They use to kick on when I turned the ac on

 

I was messing with the fans today as its summer and would like them to turn on and off with temp. I got under the car and noticed the fan switch connector disconnected. I went to connect it in between the number 6 and 8 cylinder and to my surprise the previous owner cancelled it it had a brass plug. I'm stumped as to how they had the fans kicking on when the car would reach 220? I have 3 wires. One that runs to the fans. Another one that has my 12v coming from the fuse box. Another one that it has 2 orange wires tied into each other and a pig tail coming g out of it. I looked over and over and could not figure out how they hado the fans working. Any ideas? When the ac was charged they use to kick on also when I would turn it on now it does not even do that?

 

Your best bet is going to be visiting Austinthirdgen.org and viewing their wiring schematic section. They have a factory fan wire schematic which will tell you the color wire. You should be able to use this to at least hook up the relay without the switching wire. At that point it's your choice if you want to hook the switching/energizing wire up to a switch or use the wire from the ecm as 90-92s were wired.

 

So 90sorry and 92s used wire from the ecm to control the fan? And that k you I'll look thru the schematic

 

Yes, the MAP sensor'd cars should use a wire from the ecm to energize the coil side of the relay. MAF TPI cars do too, I think. The quadrajet I think used a temp sensor in the block or head.

 

Well I messed around with it today couldn't get it. I replaced the burnt relay but I believe the connector might also need to be reolaced. I traced the wires using the diagram. To the 4 pin relay the previos owner had a 12v brown wire. The orange wire which was hot at all times. And a black with a pink stripe and he had a ground hooked up to it. I could not figure out what the black with pink stripe went too. When I connected the 12v to the black and pink wire the fans kicked on that's how I have my switch set up now. On the relay I jumped the orange wire to the black and red wire and the fans also turned on? I want to say the connector is fried. At one point when I moved the wires I felt the relay click and fans turn but they quickly shut off. So I'm assuming he wired both fans to come on with the wire from the ecm. But what would that relay be for then? Any help would be awesome thanks.

 

A relay is merely an electrically operated switch. It allows something with very low power-handling capabilities (ECM, fan switch, miniature toggle switch, etc.) to control something that is very high-power (fan motor, fog lights, etc.) Another way to look at it is a linear (moves in a line as opposed to rotating) electric motor that moves a pair (or more) of contacts.

It consists of an electromagnet - an magnet that isn't a magnet until electricity is applied, at which point it becomes one - and a moving piece of iron known as an armature, with a bunch of contacts attached to the armature. The simplest possible arrangement, which the fan relay is exactly one of, consists of a pair of contacts that don't touch when it's at rest but touch when power is applied to the coil. The contacts can carry many times as much current as what it takes to work the coil, so yet another way of looking at it therefore is, it's an electro-mechanical amplifier. Put in a little signal, get out a MUCH LARGER one.

The relay is to apply power to the fan motor, without all that power having to pass through the ECM and its wiring.

Best thing to do is quit jumping wires and/or worrying about what hack jobs some PO put on it, and PUT IT BACK TO THE FACTORY CONFIGURATION. Strip all that crap OUT, and REPAIR it by putting it back like it belongs instead of trying to "fix" whatever garbage is there now somehow. This might well involve replacing both the relay and its connector, in fact it certainly will, looking at the state those are presently in. It also CERTAINLY involves removing all of that house wiring crap (the yellow THHN wires in your pic) and all those blobs of spooge that are all over everything and the crappy little thin weenie inadequate crimp connectors poorly installed with all the exposed wire.

If memory serves, orange is the wire that brings battery to the relay, and black w/pink stripe is the wire that carries battery from the relay to the fan motor. Both of these should be LARGE, i.e. high-power. I can't recall what the other 2 wire colors are but they are SMALL, i.e. low-power, and those are the ones that go to the coil. Probably the white and brown ones but I could be wrong.

ANY relay could be used to do this, as long as its power-handling capabilities are adequate; relays are highly universal. However, rather than add hack jobs on top of hack jobs on top of more hack jobs, probably the best way to handle it would be to go the junkyard and get the FACTORY relay and connector off of another car. Find a GM car of about the same age with an electric fan. Doesn't have to be a Camaro, or even an F-body at all; in fact, FWD cars virtually ALL have electric fans for obvious reasons, and as such, are PERFECT donor vehicles. You'll likely find that the wire colors are even the same as the ones in your car, because that's kinda how GM works: those colors are somewhat standardized among all the car bodies. But it hardly matters; all YOU have to do is get the parts as described. When you get them, peel back the covering over the donor harness and get a NICE LONG section of the wire behind the connector, so that you are ASSURED that when you get it home, it's long enough to COMPLETELY replace all that crap the PO left you with. Then just splice the 2 large wires (org & blk/pink) of your car to the 2 large wires of your new connector and the 2 small wires of your car to the 2 .... you do the math.

When splicing, do the neatest most secure most reliable method you can find, UNLIKE the p****r tracks your PO left behind. For example, DO NOT twist them together and spooge them with tape; DO NOT use wire nuts; DO NOT splice in a bunch of inappropriate wire that won't stand up to the conditions in an engine compartment; DO NOT use a bunch of cheeeeeep crappy AZ type wire that melts if you gaze at it too strongly for too long or leave it out in the sun. At the very least, use good quality crimp-type butt spices and then heat-shrink and tape them up securely, or ideally, solder them and then use heat-shrink & tape. Personally I like uninsulated butt spices which I crimp and then solder, and the marine-grade heat-shrink that has the glue inside it so that it seals up PERMANENTLY without tape: that's AHELLUVALOT better than that thin weenie crap you get at AZ in those little packs hanging on a peg. ABOVE ALL you want to create a PERMANENT SECURE RELIABLE PERMANENT RELIABLE PERMANENT PERMANENT connection, NOT just another half-a$$ed mess that's just going to go intermittent again and burn up again and fail again and cause trouble again and make you have to do it all over again and again. (did I mention "permanent" and "again"? you want the one, NOT the other) Do it RIGHT, do it ONCE, put it behind you and never have to worry about it again.

Remember, it's just a car; the absolute simplest kind of electrical system there is. There is NOTHING complicated or hard to understand about it. Once you put all the "it's hard" "I don't get it" "I never was good at math in school" and similar crap OUT OF YOUR MIND, you'd be AMAZED at how eeeeeeeezy it REALLY is.

 

Got it. Yes I'm looking for a connector I'll go to the junk yards maybe Tuesday when they are open. Yea the previous owner left a mess here. But what I did notice is he didn't hack into the fan relay all those wires are intact. He simply connected into the fusible link. I've confirmed the thin brown wire is from the fuse box cause when I pull the fuse I don't get power to it. He had a seperate ground going to the 4 pin relay that use to be there but I took it out. Then he had the black with pink stripe going into it. Yes I'll have to start cleaning all this mess up it looks terrible and crappy. So I'll have to figure out where those 3 wires went to be able to put it back to stock.

 

The wire that comes from the fuse box is probably some sort of switched ignition; not sure what fuse or ckt it might have come from, but that would be the source in any case. The other would be the signal from the ECM and/or fan temp switch. The brown will thus have ignition (battery) on it during all times when the fan might be commanded; the white wire will be grounded by the other things to give the command.

Some people should simply not be allowed to own a pair of dykes. Or, maybe there should be a license, where you have to take a course and pass some kind of a test before you can buy them. Whatever the details, the world would be a better place if (a) stoooopid people could be prevented from hacking things up like that; and (b) electricity was a REQUIRED course in school without which you couldn't graduate. For something that's so universally present in our lives, it makes no sense whatsoever that we should not be educating our future citizens in how it works and how to handle it.

 

I've confirmed 2 things the fan temp switch is cancelled. I ran a continuity test it's been cancelled the wire is just hanging there and has been cut and the place where the switch goes has been plugged. The brown wire with the 12v is coming from the fan fuse when I pull the fan fuse the power is gone. The black and pink wire powers the fans. Yes I agree some ppl should just not be allowed anywhere near this kind of stuff they just make a mess of everything. From what I read the green and white wire is the one from the ecm. That is still intact to the fan relay

 

Sounds good so far.

If the fan sw wire is still there, you can put a new pigtail on it, remove the plug and re-install a fan switch, and get back your "failsafe" for the ECM not commanding the fan when it should do so.

Green w/white tracer should indeed be the fan "command" signal wire. So there you have your relay wiring... brown or tan (prolly tan) and grn/wht to the coil, org & blk/pink to the contacts.

 

But the green with white tracer wire is still connected to the fan relay. So I should install a fan switch with the wires.... I have my fusible link wire...... my 12v.....and fans....and just run a ground to it. To have an extra switch in case my fan relay fails again

 

The grn/wht wire has 2 ends.

Hook up the end at the relay to the relay, and the end near the switch to the switch.

Somewhere in the bowels of the beast there's a 3rd connection, which goes off toward the ECM. Just like the fan switch, the ECM grounds it to operate the relay and turn on the fan.

Yes you could add a 4th connection to that multiple and connect it to a switch whose other contact goes to ground, such that when the switch is on, the relay operates and sends power to the motor. No need for anything extra about fusibles and so forth; all that stuff should just be hooked back up like it came and left as-is.

 

Well I'll have to find the 2nd end to connect it to a relay. I'm going to install the connector when I get it and I'll post back here to see if it fixed the fans coming on. I'm going to order thru the wiring when I get this fixed. To make sure this doesn't happen again.

 

The fan sw was on the pass side between the #6 & #8 plugs, so most likely, you will find it in a harness in that area somewhere even if cut off. Probably the one running between that valve cover and the intake. It's probably in the split loom farther back, just cut off someplace. Might be worthwhile to get a section of that color of wire off of the same donor car the relay connector comes from, just to keep it all "right" for future troubleshooting or whatever.

 

Yes the fan switch connector is still there they didn't cut it out its just hanging there. The white wire in the above 1st picture is the other end so at least they left it there to find.

 

I replaced the relay and connector and nothing. I noticed I had no power in the orange wire on my relay once I put a jumper from my 12v to the orange wire on the relay the fans started to turn on and off. That's why they had the 2nd relay working. They could not get power to the orange wire. I also confirmed the 12v on my new fan relay plug is the same wire they tapped into to get power to the other relay. With a 195 degree t stat what would be a good temp to set for the fans to come on at? 215 maybe and off at 210?

 

I found it it was a connector by the battery it has a red and the orange wire it came loose from the fusible link from the batteryg wire and grounded that's what burned the relay and plug. What is this plug called? I need the connector both sides of it it also burned. Or can I just cancel the plug and put a fusible link junction box there? Something good like the pic above

 

Or can I run a wire direct from the battery with a Inline fuse to the orange wire on the connector?

 

I haven't really been following all this wiring confusion, but fan relays are pretty simple. Each one has four wires going to it. One is a largish wire providing 12 volts from the battery or a junction block. The other large one often black with red stripe should go to the fan positive terminal. other fan terminal to ground. Small gray or brown wire to relay provides 12 volts with the key on. The other usually green with white stripe wire provides the ground to actuate the relay. Source comes from either fan switch or ECM to turn on the fan. That's all you need to have to make them work. No idea what all that extra wiring is doing there

 

No extra wiring. It's cause I am not getting constant power from my orange wire due to a burnt connector by my battery. I was asking if I can run a wire direct from my battery with an in line fuse to the orange wire to get power to it. When I get power to my orange wire my fans kicking on with no problem.

 

Yes, that's the wire that is supposed to supply 12 volts from the battery. No fuse needed if just going to the relay

 

This is where it came apart and inside the plug is burnt only on the orange wire. So I'm just going to run a wire from my battery to the orange wire and bypass this plug. I just don't know why it burned the previous owner must of had problems with it

 

Looks like you need another relay connector. Those wires on there look kind of short to connect to
I suspect it burnt because way too many things are hotwired in there. Have you looked at a wiring diagram to see what should and what shouldn't be there?

 

Yes it just says fusible link in the wiring diagrsm. So I know it's not powering anything else I ran a continuity test just to confirm it is the orange wire that goes into the new fan relay and connector I put in. That plug is located right by my battery.

 

All of that burnt-up stuff is because, at some time, something drew too much current.

The relay connector DID NOT burn up because the other wire broke and whatever all else. ALL of the burning-up was caused by THE SAME THING, which seems to no longer be there. Could even have been as simple as, the fan motor went bad in such a way as to draw too much current, the wiring burned up, and the PO got his dykes out and started hacking, INSTEAD OF simply repairing everything.

That connector in the last pic is really just a junction block of sorts, for distributing battery to various things. (including the fusible link for the orange wire that feeds the fan relay) Looks like everything to do with that is pretty well shot.

Rather than running a wire from the "battery" to pick up the feed, which is highly impractical, run it from the big terminal on the starter where the batt cable goes. Electrically it's the same point as "battery", but it's MUCH easier to make a good reliable permanent fail-proof connection to, than the "battery" itself. Put your fusible link right there with the rest of them, and run a BIG wire from there over to the fan relay, like about #10. You'd need a 14 ga fusible link wire.

 

Ok got it. It would not have anything going to do with the previous owner wiring both fans to turn on at the same time when the ecm tells it too maybe that's why ithey burnt? And also to set the temps would those be good temps to set them at?

 

That's a possibility; would certainly account for "too much current".

Personally, I'd leave everything at the stock temp settings. Worked fine when the car was new; no reason it shouldn't still work fine, regardless of how much the car has been "improved".

 

Got it alright I'll post back when everything is running again thanks for all ur help I appreciate it.