2-Speed FORD TAURUS fan wiring dia. and part list

[COZY Z COLE]

 

 

The two diagrams above show how to build and wire an auto relay switched 2-speed FORD TAURUS fan.

Parts needed......10 guage wire for the power circuit. 18 guage wire for the control cicuit.

Three relays..... 1) High speed relay, Tyco VF7-12V,70amps

2)Low speed relay and Aux relay, standard BOSCH relays

Two switches,,,,.1)Low speed temp. switch- Adj. Flexilite, FLX-31147 from SUMMIT.

2)High speed temp. switch from Standard Motor Products, TS-158 or TS-392.

I put the adj. low speed switch and the three relays in seperate relay boxes and mounted them in the engine comp. The high speed temp switch I mounted where one of the heater hoses went. Est. cost of parts, less the fan, is $50.00 . 10 guage wire is used in the power circuit and 18 guage in the control circuit. The 12V switched control circuit can be connected to any live connection with ignition on.

The control circuit shown is as follows..... When the temp. reaches your set low speed figure, let's say 190 deg.the low speed relay is energized thru pin 86, 85 connects to 87A of the AUX relay and pulls 30 of that relay, 87 of the low speed relay and 30 are closed sending power to the fan to run at low speed.

When the temp. reaches your high speed switch figure, let's say 210 deg. pin 86 of the AUX. relay energizes thru 85 and 30 releases from 87A of the low speed relay and connects with 85 of the high speed relay which thru 87 of that relay powers the fan to run at high speed.

ARE we confused yet?????

When the temp falls below the high speed swich figure the AUX relay will switch back to the low speed relay.

Therfore low and high speeds will never be on at the same time and you will have the following conditions...

1) No fan on.

2) Low speed on.

3) High speed on.

 

This set-up has worked great since installation of it and I fought heat problems for a year because of my blower set-up before this change and NO in dash switches.........

 

LARRY

[Guest 305240]

Thanks Larry. I have simuliar diagrams, but this explains it in more detail.

[DaleMX]

Thanks Larry, I needed that and was going to research it. You saved me some time.

[Guest PROJECTRB240SX]

Are You Using Three Relays For Faster Action Or For Isolation?

 

I Don't See Why You Can Achieve The Same Results With One Spdt And One Spst? Don't Get Me Wrong What You Did Was Perfect But It Seems Alittle More Complicated Than Needs To Be.

 

How Many Amps Does Either Speed Draw?

[spotfitz]

Excellent job Larry.

If I ever get an the engine bay harness back in my Z I'll have to look this post up to rewire my "high only" circuit.

Correct me if I'm wrong, but the way you have it you could also connect the a/c compressor signal into the aux relay to turn on the high speed just for when the compressor turns on aswell. It should just bypass the thermo switches. Living in Texas a/c isn't an option, it's a life style.

Thanks for posting this.

[waynekarnes]

thank Larry ... i copied the written instructions, saved the pix , then sent the whole thing with the pix as attachments to myself in an email ... can print it up later ...

 

should save my brain from a few blisters ;-}

[240Z2NV]

Thanks for sharing!! It's so great when someone provides those kind of details (part numbers, source, $$). I was going to use the JTR recommended Volvo fan relay that I found at the JY; nevertheless, this is great info.

P.S. I'm a stone's throw down the fwy in Vallejo. You should bring your hybrid by sometime, and give me your assessment of my project (still on the rotisserie after a year!!)

[pparaska]

The "auxilliary relay" (the third one, so to speak) is functioning as an exclusive OR switch, so that only one relay (high or low speed) is energized at one time (or neither, but never both).

 

If the Taurus 2 spd fan uses the same motor as the Mustang GT (1998 or so) 2 spd fan, like I have, the high speed pulls about 35 amps, the low speed about 20 amps. I measured this on my setup, with a fully charged battery, but the engine wasn't ready to run at that time.

 

I used 2 VF4 automotive relays (typical 1" sqaure cube relay that you see everywhere in 90s cars) in parallel for the high speed function, since they are really rated at 30-40 amps depending on the design and model. I did this because I felt that 35 amps was just a bit much to ask of the relay. The GT mustang uses a relay that is internal to the fan control unit. Not sure what is in there, but the fuse for the fan is 60amps.

 

I found this 80amp automotive relay that would be a good choice for the high speed part of the circuit, but it's only SPST. But that's all that's needed for Larry's circuit anyway:

http://www.newark.com/30M9206/electromechanical-industrial-control/product.us0?sku=DURAKOOL-DG85C-8021-76-1012

 

You'd have to source the socket and terminals for the socket though. These use 3/8" terminals for the switched part.

 

Here's another available 70Aamp relay:

http://www.mouser.com/Search/ProductDetail.aspx?qs=mTeSeKeuVA6HHc5cJinlYg%3d%3d

 

I'm guessing that this has the same terminal configuration as the VF7 relay below, and the sockets terminals would interchange.

 

There USED TO BE (not sure if it's still available) a VF7 relay that looks the same as the VF4 relay, except uses 3/8" wide flat blade connector tangs for the 30 and 87 (switched) terminals. You can find the VF7 really pretty easily online, but finding the sockets and crimp connectors for them is a bit difficult. That'd be another option.

 

VF7 relays: http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=94F6087&N=0#

 

(They have the specs wrong on their online catalog. Click the link to the spec sheet to see it's actual specs)

 

Here is the harness plug (plastic part, holds the female spade terminals):

http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=90F8248&N=0

 

Then you need some .250" terminals for the plug (85 and 86, coil terminals):

http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=33B9009&N=0

 

And some .375" terminals for the plug (30 and 87, switched terminals):

http://www.newark.com/NewarkWebCommerce/newark/en_US/endecaSearch/partDetail.jsp?SKU=50F1000&N=0

 

There are surely other relays, etc., including the Volvo JY part JTR recommends.

[Guest PROJECTRB240SX]

Thanks For Clearing That Up.....

 

I Was Just Assuming You Could Use A High Speed Spdt For Your High Speed When Energized, Than When Not Energized Run It To A Second Spst Relay For The Low Speed.

[onovakind67]

Are You Using Three Relays For Faster Action Or For Isolation?

 

I Don't See Why You Can Achieve The Same Results With One Spdt And One Spst? Don't Get Me Wrong What You Did Was Perfect But It Seems Alittle More Complicated Than Needs To Be.

 

How Many Amps Does Either Speed Draw?

 

You can use only 2 relays and simplify the schematic a little, but when I wired Larry's car I only had the 70A relays in the SPST configuration.

 

If you use the 2 relay configuration, you have all the fan current running through one set of form C contacts and run the risk of losing both speeds with the failure of one relay. The same risk is run with the 3 relay setup, but the current switched is less than 1% of the fan current and the chances of failure are greatly reduced.

[pparaska]

Great point about the two relay setup - I sat down after seeing this post and saw that you could get away with just two relays (if the one doing the XOR logic and the high speed winding current switching had a SPDT configuration):

 

 

Like onovakind67 pointed out, if the high speed relay (Form C) fails, (and the terminal 30 to 87a connection is part of the failure) then this circuit would totally fail to turn on the fan in either speed.

 

There aren't any VF7 Type C relays (Form C, SPDT) available from what I can tell, so if you did want to do the above circuit, you'd have to find a SPDT relay that could handle about 60 amps across the normally open contacts. That's why I used two VF4s in parallel for the high speed function.

[COZY Z COLE]

Thanks for all the comments on my "crude" drawings and write-up of this set-up. I'm just the messenger on this as member, onovakind, is the electrical and tuning guru. Maybe he'll let me post up his NOVA that he set up and runs yearly in MEXICO in the, La Carrera Panamericana, road race that covers many days and draws cars from all over. He has placed very high in it and won many awards.

 

 

Keep in mind that I posted this as " one " way to do non-in-dash switching and would be glad to see other 2-SPEED switching methods of accomplishing that task.....

 

LARRY

[auxilary]

http://highrpm.org/howto/taurus%20fan%20install/taurusfan.HTML

[COZY Z COLE]

auxilary, if you read that article they could only hook up one speed and they choose high speed only to come on at 200 deg. The reason for a 2 speed set-up that I have is that the low speed is on most of the time and motor longevity is greatly increased. AS a side note they hooked up the AC to trigger the fan and while setting in a race line, turned the ign. and AC to on and ran the bat. down and needed a push jump.

 

 

LARRY

[Guest deadzoneman]

hello i have a 78 chevy 4x4 i need to install a electric fan and i dont know much about it the fan i have has 3 wire connecter and i want to install it so the fan kicks on at 180 degrees or so the wiring diagram i found doesnt show the fan has 3 wires so if someone can give me a 3 wire diagram and tell me all the things i need to buy for this project and give me a good diagram step by step it would be appreciated

[waynekarnes]

i slightly modified cozy's plans.

 

i used a 180 degree fan switch and a 203 degree fan switch. one on the water pump, other on manifold.

 

this is on my scarab z car.

 

same concept will work on the L6.

 

fan control switches are available on ebay.

 

cozy's set up works great. fully automatic, no idiot switches inside the car.

 

there is another set up posted on the web, turns fan on at low rpms, off at high with an override when temps reach 200. cool but more work than i wanted to do.

 

if schematics don't show, go do a search in the chevy v8 section of here. look under cozycole or taurus fan.

 

good luck, wayne

 

from cozy cole.

 

The two diagrams above show how to build and wire an auto relay switched 2-speed FORD TAURUS fan.

Parts needed......10 guage wire for the power circuit. 18 guage wire for the control cicuit.

Three relays..... 1) High speed relay, Tyco VF7-12V,70amps

2)Low speed relay and Aux relay, standard BOSCH relays

Two switches,,,,.1)Low speed temp. switch- Adj. Flexilite, FLX-31147 from SUMMIT.

2)High speed temp. switch from Standard Motor Products, TS-158 or TS-392.

I put the adj. low speed switch and the three relays in seperate relay boxes and mounted them in the engine comp. The high speed temp switch I mounted where one of the heater hoses went. Est. cost of parts, less the fan, is $50.00 . 10 guage wire is used in the power circuit and 18 guage in the control circuit. The 12V switched control circuit can be connected to any live connection with ignition on.

The control circuit shown is as follows..... When the temp. reaches your set low speed figure, let's say 190 deg.the low speed relay is energized thru pin 86, 85 connects to 87A of the AUX relay and pulls 30 of that relay, 87 of the low speed relay and 30 are closed sending power to the fan to run at low speed.

When the temp. reaches your high speed switch figure, let's say 210 deg. pin 86 of the AUX. relay energizes thru 85 and 30 releases from 87A of the low speed relay and connects with 85 of the high speed relay which thru 87 of that relay powers the fan to run at high speed.

ARE we confused yet?????

When the temp falls below the high speed swich figure the AUX relay will switch back to the low speed relay.

Therfore low and high speeds will never be on at the same time and you will have the following conditions...

1) No fan on.

2) Low speed on.

3) High speed on.

[bschiltz]

Would something like this work for the high speed relay? http://cgi.ebay.com/ebaymotors/BOSCH-RELAY-75-AMP-12V-NEW-HEAVY-DUTY-HIGH-CURRENT_W0QQcmdZViewItemQQcategoryZ42606QQihZ018QQitemZ280113440257QQrdZ1

[waynekarnes]

that would work perfectly and as the wiring screws to the lugs, you would not have to use a socket for it.

[Lewis Maudlin]

I went to O'Reilly auto parts and for $30 or $35 plus tax, I got a univeral two speed fan control unit. It has one of those annoying temp sensors that you insert in between the radiator fins, but other than that, it is great. It is also adjustable.

[280zwitha383]

I hate to bring this down to such a basic level.... but, what you are saying is that a regular 30-40 amp relay won't get you the "high speed" (why I'm not really sure if at high speed the fan only pulls 35 amps) so putting a 60+ amp relay is the only way to get the most out of the fan. I have a two speed fan from a '98 (?) Taurus and I'm just running a toggle switch to a 30 to/or 40 amp relay. I remember Hanns saying he was wondering if one of these things would cool his twin turbo and then, when he got it going, saying that it blows like a volcano or something like that and mine certainly doesn't pull THAT much air.