Aux Fan pin 99 s-10

[Eat-Pez]

OK, so fan #1 plugs into the 42 slot...where does fan #1 plug in to?

Fan #1 relay control plugs into BLUE 42.

BLUE 42 to relay pin 85
key on power to relay pin 86
10ga wire from 30A fused source to pin 30
10ga fan power wire to relay pin 87

Ground the other side of your fan motor.

That will give you low speed fan control. If you have a 2 speed fan, do the same but pin 85 will go to RED 33 on your second relay instead. You'll need to figure out what power wire is your is your low and high fan power wires, and hook your relays up accordingly.

OK, so fan #1 plugs into the 42 slot...where does fan #1 plug in to?And, how do you make the computer turn the fans on when the AC is running?

The PCM will do that automaticly by turning on your rad fans. Since your rad is sandwiched between your fans and your AC condensor, your rad fans will double as your condensor fans. If you still want a fan on your condesor, I would wire another relay to be controlled when your AC compressor turns on (controlled by the AC compressor wire) or just another fan controlled by your fan relays, since they'll come on with your AC anyway.

[Rockrz]

Fan #1 relay control plugs into BLUE 42

OK, thanks...I meant to ask in my previous post...

What slot does fan #2 plug in to?

I was hoping to have fan #1 come on at a certain temp,
and fan #2 come on at a little higher temp which hopefully
will only be when idling a long time, or in slow start & go traffic

[Eat-Pez]

blue 42 for low, red 33 for high. I've used blue 42 to control a 1 speed fan and it works. I set HPT to control fan 1 turn on temp where I want it, and fan 2 turn on temp at 255.

.

[Rockrz]

I must have missed that...thanks!

Now, all I gotta do is figure out what kind of high quality
relay to use and how to wire all that up

I assume the signal wire goes to the relay, and tells
the relay when to let the power source come thru
and turn on the fans, right?

[Eat-Pez]

Exactly. See post 21 for relay wiring instructions.

[Rockrz]

The PCM will do that automaticly by turning on your rad fans. Since your rad is sandwiched between your fans and your AC condensor, your rad fans will double as your condensor fans. If you still want a fan on your condesor, I would wire another relay to be controlled when your AC compressor turns on (controlled by the AC compressor wire) or just another fan controlled by your fan relays, since they'll come on with your AC anyway.

I know I would need to wire a relay in, but having never done that
before, I wouldn't know how.

I guess I need to find some pictures of somebody wiring something
like this up. It's bound to exist on the net somewhere, so I'll keep looking.

[Eat-Pez]

I use these, or ones like these

http://cgi.ebay.com/ebaymotors/10-PA...1%7C240%3A1318

You can see on the relay, there is a diagram. Pins 85 and 86 are the control (coil) pins. Basically, there is an electromagnet between them that controls a switch connected to pin 30. At rest, pin 30 is connected to pin 87a.

When you feed power 85 and ground to 86 (or visa versa... it really doesn't matter), it triggers the switch and connects pin 30 to pin 87.

So, since the PCM delivers a ground on the BLUE 42 to turn the fans on, you need to connect that to pin 85 and a key on power source to pin 86. that way, when you have the key on AND the PCM tells the fan to come on, then the relay will actuate.

Connect your fused power source to pin 30, then the fan power source to pin 87.

The pin #s are labled on the bottom of the relay.

[Rockrz]

OK, thanks...that's enough information there that I should be able
to figure out how to wire things up.

The only problem I can think of from here is where to tie into
a power source that's "key on" only.

Don't dual fans pull quite a bit of power? I'd need to find a
power source that is a pretty thick wire, right?

[Eat-Pez]

Get the key on power from your fuse box. Any pink wire will do. And the key on isn't for power for the fans, its for the coil in the relay. That way, your relay isn't triggered when your car is off. It doesn't make much sence, since your fans are controlled by your PCM, but even if your key is off and the temps are high enough, the PCM leaves the wire grounded. Since the PCM won't turn the fans off when you turn the key off, the other side of the coil will have to do it. That's where the key on power comes into play.

For my Astro, there are some studs on the outside of the fuse box that I used for my fan power source. Run a thick wire there.

[Rockrz]

Get the key on power from your fuse box. Any pink wire will do.

That's a solid pink wire, that has no white stripe, or any other
color stripe on it?

Since I'm going to have two fans...can I run two wires from the pink
wire...one to each of the individual relays that control each fan?

Or, do I need a different pink wire for each relay?

[Eat-Pez]

solid pink. You can get them from the same source. The coil doesn't draw that much current. You could run one wire to the relays, then jump from one relay to the next.

[Rockrz]

OK, thanx for the replies....I may have enough to actually do this.

[Rockrz]

I found a wiring diagram last night on Spal's website that I think will work.
I've attached that diagram to this post for viewing

I have an almost new Spal 11in dual fan setup I was using on my '96 S10
(same engine, etc) that worked great using the Flex-A-Lite electronic
controller.

I don't see any reason to have to go back using an aftermarket controller
since the PCM can run the dual fans just like many GM cars come from the
factory.

According to previous posts...the signal wire for Fan #1 can plug into slot
#42 on the PCM, and Fan #2 can plug into slot #33 on the PCM

My question is...looking at the diagram attached to this message, can I
simply redirect the signal wires shown in the diagram going to the temp
sensor...to the PCM?

Does this sound like it'll work?

[Eddie-98GTP]

Yes, that should work just fine. The temp switch grounds the relay, the PCM will do the same thing.

[Rockrz]

Great! Glad I finally found something visual to go on...
You know how us shade tree machanics are

[Cumulus102]

Just bought my 2003 S10. 101K, runs great (except for occasional ABS lite). I do not like the jet noise everytime I step on the gas, and, obtw speaking of that, I bought the truck thinking I am going to get somewhere around 20 MPG like my friend with his 2001 4.3 swears, not! Not sure but I will bet I get closer to 12, and I do not drive hard at all!

Ok, real question with regard to the blue 42 and red 33 discussion. Haven't played with the PCM yet, but before I disconnect the connector, should I disconnect the power or take any other precautions? I heard something could happen with the air bags?

When you say add a pin, are you referring to adding an actual metal pin install or just connecting up to an existing? I can see without removing that not all pins are wired. If I have to add a connector pin, where do I get that from?

Thanks.

[Rockrz]

When you say add a pin, are you referring to adding an actual metal pin install or just connecting up to an existing? I can see without removing that not all pins are wired. If I have to add a connector pin, where do I get that from?

Excellent question. Please lemme know too if/when you find that out.

On my truck, I've measured fual mileage numerous times and I consistantly
get 17 to 18 in town and 21 to 22 out on the highway and this is with
the OE fan.

So, I should get slightly better once I go to an electric fan

[VORTECMAX]

When you say add a pin, are you referring to adding an actual metal pin install or just connecting up to an existing? I can see without removing that not all pins are wired. If I have to add a connector pin, where do I get that from?

Thanks.

You need to physically add a Pin... You can get them from www.eficonnection.com Click on terminals...

[Rockrz]

k00L....which one should be purchased?

[VORTECMAX]

Micropack-100W... Purchase either the 18 gauge terminal or 22-20 gauge terminal. It depends on which size wire you are going to be using...