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Will this dual Volvo relay power this fan

23K views 16 replies 4 participants last post by  EOD Guy 
#1 ·

I think this is a 30 amp relay based on the #30 input and the 10awd wire -




Bmw dual temp sensor
91°c on the low side
104°c on the high side
14mmx1.5 .........tap a 1/2" brass plug and run this on the intake or the top of the thermostat housing -




This fan came off of a 93 Mercury cougar xr7 with a 4.6......it is a two speed fan-


I'm trying to make sure the electrical side of this will work. It's not the mark Viii fan with the white plug and it's not the Taurus fan. I believe it's a hybrid of some sort.
taurus motor with mark Viii blades. Maybe an RF24

If you look at the wires coming out of the fan, they look like 8 gauge wire. The relay has 10 gauge coming into it and going out to the fan for both speeds.
I'm guessing the Taurus also has 8 gauge and people are running the Taurus fan with this relay. I'm NOT going to get a controller or something high dollar to control all of this. I would just run 2 separate 40 and 50 amp relays with a self resting breaker....

2nd question is.....is the high side of the dual temp gauge too hot for the second speed
195 for the first speed and 219 for the second. The other sensor everyone runs is a 99°c (210°F)
I happened to have one on hand from my car.
 
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#2 ·
I'm not understanding your reference to using both a 40 and 50 amp relay? The Volvo relay would suffice to run the fan on either low or high speed. I would wire the 40a resettable breaker between the battery and the Volvo relay red input wire, which would supply the power for fan. However, if the water temp is above 195* when you turn off the ignition, the fan may continue to run until the temp is below the 195* sensor turn on temp, depending on how your sensor operates. To remedy this, you could install a relay between the breaker and the Volvo relay that could be connected to the ignition switch power that would interrupt the battery power to the Volvo relay. This relay would function basically as a switch to terminate the battery power to the Volvo relay when the ignition is turned off regardless of the engine temp.

As for the high speed temp, I would probably lean towards using the 210* sensor. Not knowing what type of motor the fan is going on, hopefully you will only reach the high speed temp in stop and go traffic on hot days.
 
#3 ·
what a weird and creative relay..

pin 30.. is power in..

the Yellow and White stripe wire grounded turns on the Green wire...

the Yellow wire turns on the RED wire only when the yellow and white wire is grounded and the the green wire is powered up..

please pay attention to how the relay control windings are grounded..

you may want to assemble this set up on your work bench with a battery to test it.. using a switche connected to the yellow and white wire and the other switch to the yellow wire.. both of those connected to ground..




wow... strange..

ford uses 2 30 amp relays to power the low side fan and 2 30 amp relays to power the high side fan.. in the relay control modules mounted under the hood.. i cannot think what they call them..

what is really strange is the ford relay module uses positive to control the low speed fan relay windings and negative to control the high speed fan relay windings. they actually have a voltage inverter on the circuit board . but this is just beyond what you are doing..


on some models... ford actually uses a BREAKING relay.. that the control circuit is wired in parallel with the low relays control circuit..

so when you turn on the low relays.. the braking relay switches also.. connecting the ground side of the fan to the fan.. when the breaking relay and the low relay is off... the braking relay disconnects the ground side of the fan and runs that to the low fan positive wiring.. so the fan goes into braking mode. but that is beyond what you are working with.. braking mode stops the fan from spinning in the wind... prevents it from freewheeling when its not powered.. and stops it from spinning so fast that the bearings are damaged or overheated.. shortening its life under warranty.. resulting in additional engine failures under warranty.. FYI..

i hijacked your image and added the wiring diagram of that relay to it..

this relay looks like it opens the green low speed fan wiring when the high speed relay red wire is switched on..

where ford powers the low speed fan windings and then adds the high speed fan power at the same time..

you might hook up the RED and the GREEN wire to some 1156 light bulbs or to a pair of 1157.. to see what happens.. it's really wired strange..

you might be better off with a pair of 70 amp 12 volt relays.. or even figuring out how to wire the ford relay module to power your fans..
 

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#4 ·
The reason for running a 40 and 50 amp relays....they would replace the Volvo relay. And give some extra for voltage spike on start up as the fan produces 40-50 amps.

The low side runs around 30 amps and the high side runs at 40. So I don't know if the 30 amp Volvo relay everyone is using will power the high side well.

I am going to let the fan run after the car is shut off. I'm also upgrading the alternator to the cs144 high amp to keep up with all of this.

The Volvo relay is like a hybrid of a 3 pin relay and a 5 pin. The 3 pin relay shares power to the switch and the load .....like this Volvo does....
......the 5 pin switches one hot To the other like between 87-87a.
It's ground triggered by the temp sensor. The temp sensor has 3 wires...one main ground and the two triggers. I'll mock this all up to my jump box.

My concern is the amps of the fan and will that relay hold them. I've heard it will run the Taurus fan just fine and the amps are similar. This being a Taurus fan motor. If it had the Lincoln motor I probably wouldn't use it.

The 40amp breaker will be between the battery and the relay. However.....with it being 30 amp wire and relay. Wouldn't the wires burn before the breaker ever kicked. The short distance of this 10 gauge wire should hold the amps I guess.
The fan has 8 gauge.

You think this Volvo relay will run this fan? Without overloading it.

I will go with the 210° sensor.
The engine is a 350 Chevy with a 3 core radiator. My clutch fan does fine but I want to be able to run 2mph in 110° heat.
 
#5 ·
all i can say is BENCH TEST IT as a complete set up..

check for voltage drop..

power it with a battery charger... so you can see the amp draw.. that might be too high a voltage unless you are using the battery charger to keep the battery at around 14.4 volts.. to duplicate the alternator output and almost 2 volts increase over what the battery can supply..

don't forget to mount the fan the actual distance from an actual radiator to duplicate the restriction trying to pull air thru a radiator will apply to the motor.

its just a thought.... kinda a dyno test before putting it in.. just my two cents.. better than my NO SENSE..
 
#6 · (Edited)
I believe, according to the diagram Wayne provided:

A1 is power in (Red)
B1 is a switched Ground (Yel/Wht) and turns on C1 (Green) Low speed power out
B2 is a switched Ground (Yel) and turns on C2 (Red) Hi speed power out

When B2 is grounded, it energizes the relay, provides pwr to C2 (hi speed) and then removes power from C1 (low speed)

Both B1 and B2 are controlled by the computer, the computer receives the engines temp state from the temp sensors etc....
the BWM dual temp sensor may work as a substitute for the Volvo computer etc..... if it provides two separate "turn-on" states........ 91 and 104 degrees etc......

I used a dual fan setup out of a 4th gen Camaro and a Dakota Digital dual fan controller..... they are proud of it tho'.

Here is a simplified relay diagram with a bypass switch. I use 50-70 amp relays for just about everything doing with hi amp draw apps like cooling fans....IMO a 50 amp relay will not fry on a 30 -40 amp draw.

I do not recommend you running your fans after engine shut down with out a timer. I used to have a bypass switch that I used to run after shut down etc...... a few times I came back to a dead battery..... well that's when I installed the Dakota controller, it basically lets you adjust every aspect of controlling your fan system.... 1 or 2 fans, on - off at any temp you choose. Just wish it wasn't so pricey.
 

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#7 ·
I know the Volvo relay seems to be the standard way to control the Taurus fans, but I couldn't find any amp specs for the Volvo relay. If you are going to use individual high amp relays to power the fan, I always prefer to use good name brand relays, such as Hella and not rely on the cheapest one's out there. I might try something like this:


next time I need a high amp relay, it might be overkill, but the current would be controlled by the power fuse size or circuit breaker rating you install from the battery. If a small size is a requirement, this might not be the one to use, but I like the stud connection terminals vs. the push on terminals.

Also, if the fan came with 8g wiring, I would use 8g throughout the power circuit, I'm of the opinion that the vehicle manufacturer knows more about what is required electrically than I do, and they don't spend any money on unnecessarily upgrading any parts that don't need it and it would give me piece of mind so that I was never second quessing whether 10g was working fine or not.
 
#8 ·
I think I'm going to skip the Volvo relay and go with the Bosch high amp set up. I'll still run the dual temp switch to trigger the relays but I'll get a lower temp switch.

I couldn't find a Taurus fan, which would be better as I already have all the stuff to wire it up.
I agree. The wire is just too big on that fan to trust the Volvo relay. They have smaller wires going to it to power a smaller fan.

The Volvo electric fan and the Taurus electric fan are the same fan with the same part number.
This xr7 fan is bigger and draws more amps. I don't think the Volvo relay would be safe in this case.

I'm guessing the xr7 fan was computer switched as well.
I either get a Taurus fan for $30 or a set of high amp relays, heavier wire, circuit breaker for $30

........so I'm upgrading to 70+ amp relays for both sides, 8awg wire, and a circuit breaker.
Which circuit breaker would you recommend for 8awg wire.
40amp?

Looking at that relay.....is there a way to enclose it to protect the terminals or a box style relay.

The new way I will wire it is 2 relays......each controlled by one wire on the dual temps sensor. When the ground switches in the sensor it should shut one off and turn the other on. The transition won't be as smooth unfortunately.
Maybe just getting a Taurus fan might be more simple in this case
 
#9 ·
for which fuse/ fusible link... look at the fans original application wiring diagrams or owners manual.. if you post the exact year. make model. i can reverse engineer the fuse rating for you .. no use blowing it out..


this is a handy chart about bosch relays.. it shows some of the dozens of versions and the internal switch configurations... yes.. there are a bunch of different internal configurations..

http://aa-boschap-sg.resource.bosch...ories__auto_parts/MKG3_Relaisposter_de_GZ.pdf

and the online BOSCH RELAY catalog and selector website..

Relay online catalog
 
#10 ·
I use this type CB a lot

Buss Brand Marine Grade Heavy Duty Manual Reset 40 Amp Circuit Breaker 25540 | eBay

A good source for hi-amp relays...... any stereo install shop.
I also get the fan relays out of junkers.

As far as the temp sensor..... bench top a couple of 12v lights and a battery to your temp sensor, then using a thermometer and a boiling pan of water and see if the both lights come on and if the lower one shuts off etc........

The Camaro dual fans are small and take up approx. the same space a lg single fan. I have used them on several projects.

I run 10g on my fans...... just because the insulation is of a larger diameter.... doesn't mean the wire inside it is.
 
#11 · (Edited)
I've read that the Volvo relay is rated at 60 amps.....and it makes sense if Volvo factored in the start up spike. But why put 10 awg wire on a 60 amp rated relay?
I've also read that this xr7 (thunderbird) fan is a Taurus fan motor with mark Viii blades. If it pulls the same as the Taurus fan then it's fine. If it is the same motor....it's dealing with bigger blades and more air than the Taurus fan does and therefore drawing more amps. It's not the amps or air draw the mark 7 has so it won't be as hard on the system. It does however have bigger 8 awg wires. And those wires don't match the 10 awg wires on the relay. I think the relay actually had a 30 amp breaker. The Taurus fan does....or it's a 30 amp slow fuse.

The things throwing me off is the wires going to that fan are bigger than the wires to the relay and the actual relays rating.
I know for a fact it's rated for at least 30 amps.....if it will run this fan then I want to run it.

The 10awg wire in such a short distance is rated for 40amps.
The mark 7 fan runs at 40 amps. It spikes higher but wire size won't matter for the spike. I believe it's too fast to put the wire under too much stress. It's the relay that takes all the punishment.

I can hook it up to a batter charger and watch the amp draw of it. Being it's a xr7 and is not the mark 7 fan. The amps would be less.

I don't understand voltage drop and resistance......I don't know what the original specs are.
Meaning......if I hook this up with a good alternator, will it see 14.4 volts? What drop is acceptable. This is beyond what I know electrically. I would rather understand voltage drop over a wire or system that is too small than throw parts at this thing. I don't want to get a 90 amp relay when a 70 will do or get a 70 amp relay when a 30 will do. I'm at the point where I want to know how to gauge and measure this so I can solve the problem and engineer the system according to what I have to deal with.
.

Quote
The Mark VIII is a bigger motor and draws more amps but I have yet to see anything above 45 amps even on an old fan when it’s running. It does have a momentary spike but again I have yet to see the 100 amps I hear about.
Our testing showed the Mark VIII fan ran 26-28 amps on low, with a 37-40 amp startup spike. On high it had a draw of about 32-35 amps with a 48-53 amp startup spike. This is tested with our relay kit wired with the step through configuration and a new fan. A startup from dead stop to high speed will draw higher amps.
The Taurus fan ran 24-26 amps on low, with a 32 amp startup spike
Then on high it used about 28-29 amps with a 40-45 amp startup spike. Again wired with our relay kit and a new fan.

With this information.....the Volvo relay would easily run the Taurus fan.....and it would run the mark7 fan but the specs are close and the words would have to be under 5 feet. My RF24 fan doesn't flow as much air as the mark7

If i put the relay on the system and its not enough amp.....it will burn up the relay and the wires will get hot. What I would like to understand.....that I don't understand.
Is how to tell with a volt meter if it's too small. It's the learning process I'm interested in. I know I can throw a 80 amp on there and be good. It's sitting in my Amazon shopping cart ready to buy with some Sxl 8awg wire.
I appreciate the link to that.
 
#12 ·
I've read that the Volvo relay is rated at 60 amps.....and it makes sense if Volvo factored in the start up spike. But why put 10 awg wire on a 60 amp rated relay?
I've also read that this xr7 (thunderbird) fan is a Taurus fan motor with mark Viii blades. If it pulls the same as the Taurus fan then it's fine. If it is the same motor....it's dealing with bigger blades and more air than the Taurus fan does and therefore drawing more amps. It's not the amps or air draw the mark 7 has so it won't be as hard on the system. It does however have bigger 8 awg wires. And those wires don't match the 10 awg wires on the relay. I think the relay actually had a 30 amp breaker. The Taurus fan does....or it's a 30 amp slow fuse.

The things throwing me off is the wires going to that fan are bigger than the wires to the relay and the actual relays rating.
I know for a fact it's rated for at least 30 amps.....if it will run this fan then I want to run it.

The 10awg wire in such a short distance is rated for 40amps.
The mark 7 fan runs at 40 amps. It spikes higher but wire size won't matter for the spike. I believe it's too fast to put the wire under too much stress. It's the relay that takes all the punishment.

I can hook it up to a batter charger and watch the amp draw of it. Being it's a xr7 and is not the mark 7 fan. The amps would be less.

I don't understand voltage drop and resistance......I don't know what the original specs are.
Meaning......if I hook this up with a good alternator, will it see 14.4 volts? What drop is acceptable. This is beyond what I know electrically. I would rather understand voltage drop over a wire or system that is too small than throw parts at this thing. I don't want to get a 90 amp relay when a 70 will do or get a 70 amp relay when a 30 will do. I'm at the point where I want to know how to gauge and measure this so I can solve the problem and engineer the system according to what I have to deal with.
.

Quote
The Mark VIII is a bigger motor and draws more amps but I have yet to see anything above 45 amps even on an old fan when it’s running. It does have a momentary spike but again I have yet to see the 100 amps I hear about.
Our testing showed the Mark VIII fan ran 26-28 amps on low, with a 37-40 amp startup spike. On high it had a draw of about 32-35 amps with a 48-53 amp startup spike. This is tested with our relay kit wired with the step through configuration and a new fan. A startup from dead stop to high speed will draw higher amps.
The Taurus fan ran 24-26 amps on low, with a 32 amp startup spike
Then on high it used about 28-29 amps with a 40-45 amp startup spike. Again wired with our relay kit and a new fan.

With this information.....the Volvo relay would easily run the Taurus fan.....and it would run the mark7 fan but the specs are close and the words would have to be under 5 feet. My RF24 fan doesn't flow as much air as the mark7

with that much amp load from the fan... i am so glad you are going to make it intermittent operation.. but you are also going to need to look at alternators perhaps in the 120 amp range..

this is a voltage drop test i perform on each car.. print a copy or two.. pickup your hand held digital volt meter and do your daily driver.. do all your daily drivers.. this is practice for the real thing.. and you may find small issues that a few minutes will solve problems.

http://i.imgur.com/WMDprhm.jpg

voltage drop is checking for kinks in your garden hose..

kinks in your garden hose only give you issues when you are watering the plants... there won't be enough flow because of the restriction/kink..

with the kink in the hose... with the nozzle closed.. there will be equal pressure at both ends of the hose..

with the nozzle open.. there will be less pressure at the nozzle.... this is what we are looking for with the voltage drop test... if there is a kink/Restriction/Resistance there will be slightly less voltage at the end of the wire... how much less is why we perform the voltage drop test.. copper wire has resistance... 2/100th or 4/100ths of a volt is kinda what normal lower current accessories should be.. higher load components like on test 6 alternator to battery will have more current flowing and more voltage drop..

testing between the positive battery post and the positive wire connections at the fan let you know if there is too much voltage drop in that circuit.. you can actually calculate how much current is lost..

testing between the negative electrical connection at the fan and the negative battery post will let you know if you have a good connection.

why is there 8 gauge wire in the factory ford wiring.. it allows more electron flow.. less resistance. less voltage drop.. and faster fan rotation..

70 amp relays can be had... for probably 15 bucks each.. they use larger electrical connections for the 30/87 connections ..

doing the volvo relay.. is really interesting as it prevents both power wires to the fan from being active at the same time..

i have a CRAZY stupid idea... as usual... use the volvo relay.. to control a pair of 70 amp relays... that have 8 gauge wire to the 30/87 connectors. you will at that point have a BULLET PROOF fan control system ..

i am just heading out now.. the volvo relay will probably operate the fan just fine... the professionals in us are thinking of how ford did it with 8 gauge wire and the 10 gauge or what ever it is might get hot.

let me post a wiring diagram of a ford Constant current relay module.. i am NOT saying to run one of these.. they are complex and like to blow out..

maybe i am totally wrong... go with the 30 or 40 amp relays... go with the volvo relay.. the ford CCRM uses single 40 amp relays but double connections at the CCRM connector.. so the current does not heat and melt the connector..
 

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#13 ·
All questions have been answered. Now it's a matter of choosing which direction to go. All of you have Been a great help.

I am curious why ford uses 4 relays to power this fan. 2 for each speed. What is the benefit of this.

The insulation is thicker but the wire is as well. It's definitely 8awg wire. .

I'll see if I can find a diagram. The car was a 94-95 xr7 with a 4.6 engine. That would be the best way.....just reverse engineer the original car. I didn't think of that route at all.

At this point the problem is solved. Run the 80 amp relays with awg and done....
Now I'm just looking at all the answers and learning about voltage drop, resistance, and all the stuff you guys are talking about that I don't have experience with. Things like fan break.....never heard of it. Wiring up the original module....never thought of that. Ford using 2 relays per speed....

Wiring up the original module would be the best and most complicated way. It's probably a stand alone module. Wiring diagram....original car. Even looking at the rating of relays and fuses in the original diagram would show everything since there's no specs on this fan or relay. Maybe opening it up would show more as well.
 
#14 ·
i made a mistake... the CCRM uses a Single 40 amp relay for the low speed.. and a single 40 amp relay for the high speed.. but it uses 2 wires for each thru the connector to reduce voltage drop and melting problems.. look at the CCRM wiring diagram i posted about 10 minutes ago..
 
#15 ·
I took a look at the CCRM diagram and after I looked at what a CCRM is. I see that it's a module hooked to the PCM that controls the fan and other functions.

It shows the CCRM is the same for the cars below. Some of those cars have two fans.....I know the wind star does. That's another very good fan to use but the Volvo relay won't control it. It's only good for single 2 speed fans.
The diagram you posted is the same for all of those cars. Question.....how do you know he CCRM in all of those cars is 40 amps as it doesn't specify there in that diagram.
If that is the case.....and I believe it could be. Then the cougar fan I have originally ran 40 amp relays. 2 of them......the same for some reason.
Even the Lincoln fan runs max 40 amps as well but spikes at 53. So the 80 and 70 amp relays are even overkill and would probably never wear out.

So it's safe to say that 40 amps would run my fan and 50-60 amp relay would be over kill. 40amps also explains the heavier wire. While 30 amp wire will run 40 amps over a short distance. The factory would have not done that. They would have stayed safe at 40 amp 8awg wire and ran matching relays that would be sufficient. I'm also guessing that the xr7 fan doesn't spike at 50 even on the high side. The Lincoln fan does but my fan is slower.

QUOTE:
The IRCM is the Mark VIII equivalent of the CCRM. Different part and location, but same basic role.
BTW, they are NOT interchangeable; the Mark VIII fan is speed-controlled while the Thunderbird has two speeds, low & high.


Also, that CCRM has been the same CCRM that has been used for years in a variety of vehicles.

Per Rockauto:
FORD ESCORT 1997
FORD MUSTANG (1994 - 2000)
FORD TAURUS (1996 - 1997)
FORD THUNDERBIRD (1994 - 1997)
FORD WINDSTAR (1995 - 2002)
MERCURY COUGAR (1994 - 1997)
MERCURY SABLE (1996 - 1997)
MERCURY TRACER (1997 - 1998)

Even the dual fans and the 2 speed fans could use that....but the diagram would have been different for them......maybe.

all of this is making sense now.
I can go with a continuous duty 50 or 60 amp relay with a diode and be safe.
Then run 8awg wire to the relays, battery, and fans and be good to go.

How can I tell if the 60amp relay I get is continuous duty......or are they all continuous duty. I've seen where that's not the case.....
 
#16 ·
i am the crazy guy who takes things apart to reverse engineer them to figure out how they work... what failed and why they failed. .

there are several CCRM versions with slight variations in wiring pinouts..

i have opened CCRMs and found a flock of bosch circuit board mount relays all soldered down.

if you look closely at the CCRM fan controls.. one relay is turned on with a positive voltage.. the other turned on with negative control..

as for the relays.. constant duty .. intermittent relay.. i did link several relay sites.. i usually try to use bosch relays.. i have seen 30 amp versions.. 40 amp versions.. 70 amp versions.. i am not aware of 50 or 60 amp versions.. but i don't know every brand and every part number..

potter broomfeld relays are also good quality.. there are tyco versions..

did you see the relay chart.... the lower right shows the various internal circuits available.

here are some Budget options...
12 VDC 30A SPST N.O. RELAY | All Electronics Corp.

12VDC SPDT 40A AUTOMOTIVE RELAY | All Electronics Corp.

SOCKET FOR AUTOMOTIVE RELAY | All Electronics Corp. these sockets will interlock side to side..

but they only have like 14 gauge contact wiring..

you can visit most wrecking yards and with a pocket knife.. a 7mm nut driver and a set of wire cutters.. visit the various sections and find water proof relays and sockets already wired with 8 or 10 gauge load wires.
 
#17 ·
Your money, your car, your time. I run 50 amp and 70 amp relays on cooling system and have never had one burn-out.... I've had corrosion problems but never a burn out. I use 10g wire and have never had an issue, I've wired after market, junk yards etc.... fans. If you run an AC, it's advisable you use some sort of AC-on then Hi-Fan "on" circuit. If you are traveling above 50, you really might not need a fan.......yadda, yadda..... I've use dual temp senders separate senders, all of which have plusses and minuses.

I have settled on the Dakota Digital Fan controller which fixes most of my issues for numerous projects. You still need the correct wire and relays etc........ IMO worth the high price tag.

Electronic Fan Controller 70 Amp
 
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