# [SOLVED] 97 Grand Am Cooling Fan



## Eremon1

I have a 97 Pontiac Grand Am 3.1 liter v6 (3100). The cooling fan does not come on even when the car is really hot. I have tested the fan by connecting it straight to the battery and it spins. I'm left to think its the relay, fan switch or wiring. I know there are 4 relays under the hood on the passenger side along the firewall. But I don't know which ones are which. Can't find any information on them in the owner manual or Haynes Repair manual. Also the internet doesn't seem to have much on clear information about the relays. The location of the fan switch is somewhat unclear to me as well.

So my questions are; 

1. Where are the relay(s) for the engine cooling fan?

2. Where is the engine cooling fan switch located?

I also had an idea to bypass the original circuit and wire the fan directly to the same circuit that powers everything else when the ignition is on. Would that shorten the life of the fan?


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I've bypassed the original connector to the fan and made up a wiring harness with a switch to connect straight to the battery. This is a bandaid solution until I can find where the relay and/or cooling fan switch is. 

Any information to lead me in the right direction would be greatly appreciated.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

The relay should be either on the firewall or the driver side fender.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

As I've already stated, there are 4 along the passenger side firewall. Problem is I don't know which one is which. Any ideas? Also perhaps you or somebody else may know of the location to the switch that tells the fan to come on when the engine is hot enough?


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Since you do not have access to a wiring diagram or you have difficulty in getting one, you will have to trace the wires manually. Locate the cooling fan sensor and disconnect it (usually on the rad) . Do the same thing to the connectors on all relays, by using a DVOM do a continuity test from the sensor connector pins ( ignition off) to each relay connector pin until you get a reading. 

You can also do a short cut by doing the cotter pin test (not recommended). Short out the pins on the cooling fan sensor connector to determine if it's the relay or the sensor. You will be able to hear the relay clicking when you short the pins, should the fan come on after shorting the pins then the sensor is bad, if not it's the relay. 


post back your findings.


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## pat mcgroin

*Re: 97 Grand Am Cooling Fan*

I can tell you this
It looks like a lite blue wire to the sensor and then ground.

try autozone.com

You will need to register.
If not possible please post back and we can do more

It doesnt give the exact location but we can find it.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

@octaneman

I do in fact have a wiring diagram. The problem I have is that a diagram still does not help me with the actual physical location of the sensor or the relays, the only thing it tells me is what they are connected to.

I do know how to perform the tests of relays and sensors with my DVOM, but I need their physical locations in the car.


@pat mcgroin

Given that there are literally hundreds of wires of all color under my hood, that is too vague to help at this point. Also tried autozone and only found it to be a commercial parts seller. I don't need parts till I know which ones are bad.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Eremon1

I found a component locator hope this helps you out.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Sorta, but like I said there are four relays along the firewall on the passenger side and not three like the pic you posted has. I appreciate the effort anyhow!

I can't believe it's this hard to find the location of such a simple component. I've never had this much trouble before.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

I doubt the 3.1's changed all that much, and since on this diagram its only 3 relays the last to the right, I'd check the farthest from the right if it were 4 relays like yours.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Well I've tested all four relays and they all checked out. This leads me to believe that the sensor/switch that turns the fan on when the PCM detects the correct engine temp, is not commanding the fan to come on.

So I've since bypassed the original connector and cut one out of a car at the scrapyard, then turned it into a wiring harness with a switch inside the car. The fan is now directly connected to the battery with said switch. Now I can turn on the fan when I choose. I don't mind this for the time being, but I'd really like to know where this sensor/switch is located so I can pop it out and replace it.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

The sensor switch are transistors that are inside the PCM.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I know there is a removable sensor/switch that is controlled by the PCM/ECM. For this problem I can tell this in not the place to seek answers. To many variables.

Thanks for the help anyway. Cheers.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Okay so nobody seems to know where this stupid sensor is so I've given up trying to locate it. Even the dealer couldn't tell me. (Probably just wouldn't tell me)

I've since gone with the direct connection of the battery to fan with a toggle switch to control on/off. This is just fine with me, but I can't seem to get the toggle switches to stop breaking. After a day the first one went. The second one lasted a week or so before breaking in the on position and it was warm to the touch. I'm assuming it's a current issue, but 10amp switches are all I can find anywhere. I also can not find accurate information on the amperage of a car battery. Not talking about cold cracking amps, that IS totally different. A fuse isn't going to solve the problem either since it will just blow instead of the switch which is equally as unpractical. 

What am I doing wrong? What type of switch should I use?


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## pat mcgroin

*Re: 97 Grand Am Cooling Fan*

It isnt the amperage of the battery.
It is the amperage that the fan is drawing that is causing things to heat up.

Do you have a multi meter?
You can unplug the fan and all 4 relays.
Then probe from the fan to the relay plugs to determine the trace to the correct relay.
As above try to look for a lite blue wire going to the relay.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

For the switch to get hot there are 2 possibilities. 1) The switch's amperage rating is too low for your application. 2) You hooked up 12v directly to the switch without connecting a bleeder resistor. 


A rocker switch with the same amp rating (or greater) to your fan would be the component of choice. Keep in mind that your connection to the switch must run through a fuse first, and the positive (HOT) is always the larger pin on the switch, connect your negative to the chassis.


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## octaneman

*Re: 97 Grand Am Cooling Fan*



Eremon1 said:


> Okay so nobody seems to know where this stupid sensor is so I've given up trying to locate it. Even the dealer couldn't tell me. (Probably just wouldn't tell me)





Possible location under your coolant resevoir tank.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Yes the connection goes from battery to fan and switch. I have the fuse in now. The switch I am currently using now(switch #3 now) is a 10amp / 250v toggle switch. I have both negative and positive connected straight to the battery. Never heard of a bleeder-resistor before. 

Is that a certain kind of resistor or just a simple resistor hooked into the wiring on the positive lead?

Checked under the coolant reservoir and nothing there at all. In my Haynes Manual, it gives a very brief description of the sensor and has a picture of it. However it is extremely vague as to it's location. I've looked and see something that could be it but no way to verify what it actually is.

Oh yeah, and in my other car a 96 Olds Cutlass with the same 3.1 v6 and it has the sensor. On my 97 Grand Am the 3.1 is the same in most things, but there are minor differences. This is one of them.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Can you please post the picture from the Haynes manual, there may be a way to identify it's location.

A bleeder resistor is just using a normal resister, the bleeder is the reference to what it does. For example it bleeds ( drains off ) excess power so nothing gets fried. The hook up for the external fan switch can be done using a resistor or a diode. One way to connecting it is using a diode, it acts as a braking system to the fan the technical term is dynamic braking. The diode or resistor is placed across the fan terminals, so when the fan kicks over, if there is a voltage spike the diode will prevent the spike from going to other components. A diode acts as a 1 way valve, it allows current to flow in 1 direction only. 

Most common method is by using an LED ( Light emitting diode). It is used as a on\off indicator when you turn the fan switch on. By connecting the LED to the solenoid ( trigger source of the relay) then connecting all of them in a configuration of pin#30 to the fan, then connecting pin#87 to the fuse ( power source) and pin#87 to ground.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I don't understand much of what you last wrote octaneman, sorry. I don't have a picture of the manual. Don't have a camera and my scanner is toast.

I've tried putting an LED into the circuit, but when I do only the LED will come on when I flick the switch and the fan stays dead. When I remove the LED the fan works again. I don't know where to begin to determine what sort of resistor to use and can't find anything called a bleeding resistor.

Here is a diagram of my circuit. When I placed the LED it was in the switch part of the circuit on the negative lead from fan-to switch-to ground.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Eremon

In your diagram you have the switch connected directly to 12 volts, it is incorrect and the reason why your switch gets hot after a few seconds.

To make a proper connection you will need fuse, relay, switch, LED. 

Look where the pins are on your relay and you will see carefully that they are numbered, the numbers correspond to the various pin input\outputs. There are 2 methods to making a relay click on (trigger), either positive voltage or negative voltage. 


The relay consists of a coil ( pins 85 and 86) a common terminal (pin 30) 1 normally closed terminal ( pin 87a) and one normally open terminal (pin 87) 


To make your circuit work you will need to take power from your fuse box and connect the switch after the fuse. Connect your positive from the fuse box to (pin 87) of the relay and your negative to (pin 87a) of the relay. Then run your LED to the coil (pins 85 and 86). Connect the fan to the common terminal (pin 30). 

A diode is usually connected to the coil side of the relay to prevent any components from burning, or a resistor is used across the fan plug terminals. The value of the resistor is determined by how much amperage your fan motor draws.


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## octaneman

*Re: 97 Grand Am Cooling Fan*



octaneman said:


> Eremon
> 
> Connect your positive from the fuse box to (pin 87) of the relay and your negative to (pin 87a) of the relay.



Correction : Connect your power to the relay from the switch when you turn the switch on to pin 87 of the relay and your negative to pin 87a.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

That is way too complicated for me. I'm no electrician and I don't want to be!

I don't think I need the relay since the computer is no longer involved and thus the switching action of the relay is replaced by my manual toggle switch. Not to mention the amount of wire I would need to run to all those places. It would be extremely messy. Second, I still don't know for certain which relay is which since there are 4 of them.

There has to be a way to do it with the circuit I've already made. All I want is a simple toggle switch to turn fan on and off. Period. I don't mind putting in an LED or resistor. But how to I do it with my circuit?

I've since changed my circuit so that the switch is now on the positive side. As the attached pic shows. The switch gets warm but isn't over heating now. But I still would like to put in a resistor or something to help keep the switch working.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Sorry Eremon I can't change the laws of physics and there are principals in electronics that can't be ignored. Hooking up your switch directly to a power source will burn out the switch constantly, in all cases where the amperage is high the wires as well. The engineers who designed the system could also just hooked up the fan directly and avoided the hassle of putting relays and other components that are incorporated in the computer which you don't see.... They didn't because they can't. 

You don't need millions of miles of wiring to to fix your manual switch, it is already done for you. The only thing modified on the relay is the connection going to the computer. Instead of the pin going to the computer it goes to your toggle switch. If you have a wiring diagram follow it's connections and choose the best possible location for your switch. If you still don't know the location of your relay just call the parts department of any GM dealer and they'll tell you.

Note: It is not uncommon for mechanics to install toggle switches in the glove box when deciding locations, it is convenient and saves time.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Addendum:


This is how the connections should look like.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I don't understand. In digital electronics I hook switches directly to power all the time and also in home electrical, the switch is intended to interrupt power and let it flow when needed. I don't understand this at all. I get the resistor, but the rest makes no sense to me. 

I understand why they wire into all that at the factory, because they need the computer to do all the decision making involving the automated switching action.

Also, a relay if I understand correctly is nothing more than a switch itself. Therefore I really don't understand why I need to wire into the toggle and relay. Seems redundant to me.

That last schematic makes almost zero sense to me. Like I've said, I'm not professionally trained in this stuff.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Sorry if I'm difficult, but I really need to understand something in order to work with it. Right now I'm missing parts of the information on how this is supposed to work and why it isn't working for my design right now.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

I can understand your frustration and I'm trying to accommodate you as best I can without flooding you with too much technical jargon. Building circuits from scratch is not the same as installing pre-fabricated systems and hardwiring it to a given source. What you are trying to do is build a circuit from scratch by putting components A,B,C together and thinking it should automatically work, in theory you are right it should. But when it is done in practical and everything is hooked up, systems begin to heat up and fry sometimes with disastrous results leaving you scratching your head wondering why.

The reasoning behind your circuit design is correct because it does work, thinking there shouldn't be any need to add anything else why bother doing it?... Right ? Wrong, this is the trap most DYI'rs fall into because they have gaps in their information on how DC circuits work. A relay for example is a switch, but in certain applications it is a must use component, because your car's cooling system for example needs high power to drive the fan motor. Just using common switches won't be able to handle the load to switch the motor on or off. It's a difficult concept to understand at first since the relay and a toggle switch do the same thing, but the fundamental principals behind the two components is that a relay can handle a bigger load and switch multiple sources, where as a single switch handles only one source. 



Note: My apologies if I was being too presumptuous, the schematic I provided in my last post led me to believe you understood electronic diagrams.


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## pat mcgroin

*Re: 97 Grand Am Cooling Fan*

First I will say that in my 90 chevy 3.1 the temp sensor is at the thermostat housing under the throttle body..
I cant say that it hasnt been moved in 7 years, but I just went and looked for it.

In regards to a relay. I think that the best way to describe its operation is that it is an externally activated switch. It is possible for example that it could be a 400V 200A switch that only requires 12V from a siganl to activate it.
Obviously the correct relay that contains both aspects of operation is required.

The temp sensor in this case would be a variable voltage signal and would commonly be sent to the computer which would inturn decide if the time is right to activate the fan.
The computer would then issue a possibly full 12V signal to the relay in order to activate the line voltage that would actually activate the fan.
This is done so that the full amperage is not sent through the computer in order to not allow the heat that amperage creates and allow the computer to remain cool.

This heat that you are having while having it hooked externally is the same issue.
I am surprised that you ae having an issue in your setup and have a couple of questions.

In your connection what size wire is being used to the switch and its return?
Sufficient wire gauge is needed when length becomes an issue.
Since it is amperage that ultimately is running the fan as compared to voltage.
The longer the wire the more amperage and more heat will developin the wire.

Do you happen to have an Amperage guage that you can place inline on the circuit in order to determine the amperage that the fan is trying to draw?
I wouldnt think that it would draw much and the fact that you have heat issues makes me wonder if the fan is working correctly.

In you above schematic I see that your ground leads elsewhere.
In a simple circuit ground should ALWAYS be directly to the Batt.
In spite of common belief voltage runs from Neg to Pos in most cases.
(I am sure I will catch crap for this)
Regardless a clean and close ground is the best answer.
Often corrosion can impede a good ground and will alter the effect of any circuit.
If you have ever seen a car with one bright headlight this is why.

In regards to Octanemans insistance on a bleed circuit you have to remember I belive that he is looking at you using some of the existing circuitry to help allow for fan control.
if that is the option then a blled is required due to the battery having 600 amp or more of possible output.
Your fan may require 4-10 amps dependent of the amp test above.

If you want a simple circuit as you have shown above I would recommend a very strong switch and at least 14 guage or possibly 12 in order to assure proper amperage needs.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Eremon 

To calculate the resistor value for your fan motor to brake it dynamically, you will need to find out the motor wattage first. To obtain it do this;

Multiply;
Motor hp x 746 x duty cycle percentage (ie; 0.2 for 20%) = motor wattage.

Take your answer in wattage and then divide by 2 to get the resistor value.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

How do I find the motor HP? It's electric and I don't have a dyno! :wink: Plus I'm not sure what the duty cycle rating is for my fan motor.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

You will need to take the number off the fan and do research to find the specs for it from the manufacturer or a shop manual. 


please post the S/N# of the fan.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I will get that S/N# soon, work has been really busy.

Since I changed the switch to the positive side of the circuit, with the negative not connected direct to battery, the switch isn't over heating anymore. I still would like very much to connect it the way you've suggested Octaneman. I'm going to see if I can work on it over this coming weekend.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Well we had a monsoon for the weekend. I haven't been able to get near my car. It will now have to wait another week.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Ok I'm tinkering with the car again. I have drawn a diagram of the way I'm understanding your method, octaneman. Forgive me if it's bad! :wink:

If I'm correct in my understanding I can then begin to wire it up. Let me know if there is something wrong with it.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Eremon

The block diagram you drew is the way it should be done, all the safety protocols are in place.


Nicely done !


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Well thank you, but it's really just the way you said to do it. :smile:

My only issue is that I'm a bit nervous tapping into the fuse box under the hood. I'm not exactly sure how to go about it. I imagine the fuse I'd be using would be one that's already in the box?

Or can I take power from direct from battery and place a fuse between battery and the rest of circuit?


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## octaneman

*Re: 97 Grand Am Cooling Fan*



Eremon1 said:


> My only issue is that I'm a bit nervous tapping into the fuse box under the hood. I'm not exactly sure how to go about it. I imagine the fuse I'd be using would be one that's already in the box?
> 
> Or can I take power from direct from battery and place a fuse between battery and the rest of circuit?




You can take power from the battery and place a fuse, in effect you re-doing what the manufacturer has already done for you. 

There's no need to tear apart the fuse box, just use the existing circuit on the car. Find the fuse that goes to the fan and just hook up your switch to the relay on the relay side just as you have it on your block diagram. Make sure you disconnect the battery when you make your connections.

Keep us posted on your progress.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Yeah I sort of figured, but the part that confuses me is that for each fuse there is an in and an out. How do I know which wire is fuse protected and which is power coming into the fuse?


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## octaneman

*Re: 97 Grand Am Cooling Fan*

To find out which side of the fuse is the input/output you will need to do a continuity test from the fuse pin(s) to the source. Example. Suppose you want to find out which side of the fuse goes to the relay. There are 2 methods; 1) test light 2) multimeter. 

Test light method: Remove the fuse, connect your alligator clip to ground and place the tip of your test light to one of the pins and then cycle the ignition key. When the test light goes on/off the pin that is probed is the input side the other the output. 


Multimeter method: Set your multimeter to DC volts, remove the fuse and connect your negative leed to ground and positive to one of the pins, the pin that reads battery voltage is the input. 

Set your meter on ohms scale (continuity), with fuse removed connect the positive leed to one of the pins and the negative to the source you want switched (IE; relay). The meter should give a reading when the correct pin is selected. If equipped with an audible tone the meter should beep confirming the output connection.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Ok, sounds like something I can manage. Also, I just found an extra foglight 2 position toggle switch for my grand am. The kind with the LED in the switch. It has 3 leads. Is there a way I could use this switch instead?


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Yes you can, as long as the ratings on the switch are sufficient for your applications input/ output. Use a multimeter to the switch to identify it's input/output.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Okay, so I have it all hooked up the way I drew in my diagram. Nothing. No power to fan. Relay is good and it's hooked up the exact way you said. I have every wire labeled front and back so I know what is going where. Have all the pins labeled and double/triple checked. It's not working.

Are you sure this is the way it's supposed to be done? Something is wrong. If I pull the LED from pins 85 and 86 and just connect them nothing happens either. I've tested for power and it goes in but does not come out of the relay. I've tried the 10 relays I have here. They are all good.


Just to be clear, there are my connections;

Positive from fan to pin 30 on relay.

Negative from fan to pin 87a on relay.

Positive from battery to 40amp fuse then to switch then to pin 87 on relay.

LED to pins 85 and 86. Tried both polarities.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

After you made your connections did you test for 12v coming out from your switch ? I am assuming that the switch you are using has 3 prongs with an LED. On your switch there is 1 pin for ground, 1 pin for 12v input , 1 pin for the switch. The output of your switch has to be connected to the trigger pin on the relay. Connect a test light and look for power coming out from your switch, also the coil on the relay must have 12v going to it so when the switch is turned on, the trigger pin activates the relay. Before you connect everything to the fan make sure the relay switches on and there's power coming from it's output. You can hear the relay click on when you turn on the switch, if you don't hear the relay click on then there's a problem with the switch connection to the relay.



post back your findings.


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## Wrench97

*Re: 97 Grand Am Cooling Fan*

What is the LED for in the circuit?

This is how I would wire the Switch(correct me if I'm wrong I assume you just want to be able to turn the fan on and off using a toggle switch?)


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## Eremon1

*Re: 97 Grand Am Cooling Fan*



octaneman said:


> After you made your connections did you test for 12v coming out from your switch ? I am assuming that the switch you are using has 3 prongs with an LED.


No, I decided to keep it simple and go with the separate LED and switch with two prongs. Now that I look at wrench's connections to the relay I'm really confused on how it works and how to wire into it.


@Wrench
Yes I just want to toggle the fan on and off. But with the way I originally wired it from battery to switch to fan, the switch would over heat. Octaneman suggested I wire through the relay and add in an LED to draw enough current to dissipate some electrical heat. At least that is my understanding of his intention. He can step in to correct me if I don't have it understood quite right.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Eremon 


The LED acts as an indicator as well as it dissipates some current from the circuit, can you please post a picture of the switch that you are using or post the serial number including the relay so we can see the pin configuration. A two prong switch setup is not the same a three prong switch as I assumed you were going to use. You mentioned that you were going to use a fog light toggle switch with built in LED. I based the circuit setup on that type of switch, I didn't expect you would change the setup. We'll take this one step at a time to get the system up and running so there is no confusion, but we'll need to be clear on how you want it set up.

1) Do you want to pass extra relays, switches and wires or use the existing wires and relay on the car? My recommendation is to use what's on the car it will save you allot of hassles. 

2) Post the wiring diagram of your car so we'll find the quickest route without splicing unnecessary wires. 

3) Tell us where you want the switch to be readily accessible, the driver side? or passenger ? 

Once you hammer down the switches location, the rest of the setup will go very quickly.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Right, also to indicate power On.

Sorry for the confusion on which switch I am using. Here is a list of parts I am currently using in my circuit;

1 - five prong relay (Siemens VF28-35F14-Z05)
1 - two prong 10amp 250volt 2way on/off switch
1 - two wire 12v LED
1 - 40 AMP fuse
12 gauge wire

I've attached a simple diagram of how I laid out the wiring in my car physically and where the switch and LED are located in relation to the relay. Its all done, the only thing I need to know is the proper relay connections.

I repositioned the relay to the drivers side for ease. I've also attached the diagram that is printed on the side of the relay to help you determine it's pins.

To be clear, all I need to know is the correct wire connections to the relay.


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## octaneman

*Re: 97 Grand Am Cooling Fan*

Ok the configuration of the wiring will change to accommodate the single 2 prong switch that you are using. So we'll take it 1 step at a time, do not connect anything to the fan until you verify that the relay clicks on.


Take your 12v after the fuse and connect it to the switch, from the switch to pin 85, pin 86 goes to ground. Connect a jumper wire after the fuse to pin 30. So you will have 12v to the switch and 12v to to pin 30. Pins 87 and 87a will go to the fan. Connect your LED anode ( positive) to pin 85 and the cathode (negative) to ground on the relay. When you turn the switch on the relay should click and the LED turns on, then use a test light to see if power comes from the relay to the output pins.


post back the results.


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## Wrench97

*Re: 97 Grand Am Cooling Fan*

One leg of the fan has to go to ground, the ground on pin 86 will only work the relay coil.

The relay switches the power (pin 30) between pins 87 and 87a, the fan will get current from 87(a) but needs a ground to run, the led indicator would be wired the same as the fan.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

I drew up yet another diagram of how I understand what you guys are saying. I just want to make sure the theory is correct before I go put it into practice. I'm curious about a couple things;

Does pin 86 on relay go to ground? And what about pin 87? Do I leave it unconnected? Are my connections in the new diagram correct?

Also from what I can tell this relay has 87a normally closed. I assume when pin 86 gets energized that 87a goes open and 87 closes. Am I correct? If so shouldn't the fan positive be connected to 87?


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## Wrench97

*Re: 97 Grand Am Cooling Fan*

The Idea of the relay is to carry the load so it does not run through the switch, Term 30 should go directly to the 40 amp fuse, for the Led to be an indicator of when the fan is powered on the + side of the LED should go to term 87A along with the + fan wire, 87 is hot when the switch is off and not used in this application so no wire there. 85 & 86 are the coil or trigger circuit one terminal goes to neg the other to positive it makes no difference which one, or which one is switched if you wanted to make it simple use the switch on the ground side wire 86 and 30 together, then use the switch to control the ground side one leg of the switch wired to ground the other to 85 when the switch is turned on it completes the - side of the circuit pulling the relay in to connect 30 & 87A and turn the fan on.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Okay I hooked it up the way you've got there wrench97. The fan comes on when the switch is in the OFF position. When I flip it to the ON position the fan goes off. I didn't have a chance to put in the LED yet because once again it's friggen raining outside. My concern is that it's not correct and would draw current when the fan is off. True?


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## Wrench97

*Re: 97 Grand Am Cooling Fan*

Move the Fan positive wire from 87a to 87.


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## Eremon1

*Re: 97 Grand Am Cooling Fan*

Success at last! Thank you Octaneman and Wrench97!! Once again you both helped me out. Cheers!

I have it hooked up the way Wrench had me do it. The LED and switch are functioning properly. Fan comes on and goes off. Now I have to drive for a while to see if the switch still gets hot. I'll post back if it does, but for now this thread is marked Solved!


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## Wrench97

Good to hear you have running and staying cool.


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## octaneman

Good job ! :4-clap:


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## SABL

I think we have a new record for number of posts to solve a problem..... I don't even think security can come close!! Good job, guys.... well done in hanging in there until a solution is found!!


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