[86GT]

That is exactly what I found although I could not find a manufacture of the chip.

I opted to use a temp switch on the block for the low speeed and then use the EEC to control the high speed. It worked pretty well. The only downfall that i saw was the draw on the battery. Low speed was not too bad but when the high speed kicked in the draw was significant at an idle. This is even with a 130 amp alt.

I have since moved to the DCC system. It is a variable unit that is not EEC dependent. It works way better than the two speed setup. It does sound like a jet engine when I shut the car off though. LOL

The two speed setup caused heat cycling and it seemed as if I could set my watch by it. Every 4 minutes the fans would kick on. Now all of that is gone.

[WA2FAST]

So if I'm reading all of this right, I need to get a small 3a relay to drive the larger fan relay... right? I'm going to do this setup this weekend and want to make sure everything is all set and ready to go so I can minimize or eliminate trips to the store.

What settings are you using for the fan? I'm only going to be using high speed, not 2 speed... I have a Be-Cool 2 core radiator and a Be-Cool fan on it...

Any suggestions would be greatly appreciated. Thanx guys!

Don

[86GT]

You will need a 30 or 40 amp relay not a 3 amp.


I will have to see if I can find my tune that had the fan enabled to get the settings

[WA2FAST]

I know that, but I read that someone had an issue with the pin 41 triggering the fan relay... it wasn't enough juice to make the coil energized so he had to run a small relay to trigger the large fan relay.

What are the settings... my fan just turns on when I key the car, that's not right...

[86GT]

I believe I read that too. The EEC can handle 1 amp of current on pin 41. The 50amp relay is right on the verge of this. The CCRMs that I have taken apart have 40 amp relays.

The settings I use are as followed:

Fan A/C Minimum Temp Activate = 60
Fan High Speed Disable Temp = 190
Fan High Speed Enable Temp = 194
Fan High Speed Enable = 1
Fan High Speed Hysterisis = 4
Fan Low Speed Enable Temp = 174
Fan Low Speed Enable = 1
Fan Low Speed Hysterisis = 4
Fan Low Speed Min Time befor High = 10
Fan Low Speed VSS = 40
Fan Low Speed VSS Hysterisis = 5

[Brian-Mc]

In regards to the 3amp relay... yes. I had to use it to trigger the fan relay as the current supplied out of the EEC was not sufficient to power my fan relay. This maybe different than yours...

[WA2FAST]

Same here. I read what you and others ran into with the EEC not being able to trigger the coil side of the relay and didn't even try because I have a Bosch 75A relay from back when I had the Mark VIII fan in the car. I wired up a small 5A 12VDC relay and it does the job perfect. That relay then in turn closes the circuit to the ground side of the 75A power relay connected to my fan. I am so happy I finally took the time to do this A9L fan control setup, it works SO much better than the thermostat setup that I had before.

I had to screw around with the settings for the high/low fan before I figured it out, but I got it now. The hysteresis still confuses me a bit... I guess that kind of gives the A9L a touch of "logic" for that function, but who knows. It works great, that's all I know!

Thank you again for all of the help with this setup.

[JaxMustang50]

When using pin 41, does the fan run KOEO or only when KOER? I wanted to know because I am satisfied with my current setup except that I have to manually turn the fan off and on again when I start the car. I don't want to have the fan run when I turn the key only to have to immediatly shut off and then back on again when the engine starts.

[86GT]

If i remember right it will only be active if the key is on and the temperature exceeds the setpoint.

[JaxMustang50]

Even if the engine is not running? Can anyone confirm this that uses the a9l fan control? If your car is hot and you turn on the key but do not start the engine, does the fan come on? Thanks.

[silverstangboy]

I know this thread is probably old, but I wanted to add that the bosch (tyco) 75 amp relay that so many people are now using has a coil rating of 300 miliamps, sooooo. that should come in way under a spec of 1 amp for the A9L controlling circuit that Clint posted... I haven't tested this with a meter but those are the specs from tyco.

BTW clint, I love the new software, car is already running great.. can't wait to get some tuning time on my hands.

[Vortech347]

I'm using the same Tyco 75amp relay on my setup now. Can you confirm the EEC flipped it?

[pony]

I found that one of the required IC is missing. It is an 71001FB chip that can not be bought. It has been off the market for nearly four years.

I 8061 CPU is outputing the signal to the chip location but since the chip is missing, not ouptput is felt on the J1 connector. I was temped get the cip from a wreked car from the bone yard but. They are vary senitive to temperature. A good heat sink may do it while trying to un solder them, but the did a butcher job on getting them in there.

Sorry for the megabump. Do you or anyone else know what the 71001FB IC actually is? All I can find is that it comes in a 16 pin DIP package. Is it a buffer or inverter? Anyone have the datasheet? I am willing to design a simple add on circuit to enable low speed fan control if there is a demand for it. I believe Texas Instruments made these ICs and EEC-V's also used them. I found a schematic for a xsk-e7rf-3458-a1 (can't find out exactly which EEC-IV it is though http://www.merkurencyclopedia.com/EEC-I ... ematic.jpg ) and it seems to be IC5 which is exactly what IC2 is. If it's a simple buffer or inverter, it will be quite trivial to come up with an alternative IC to solder in.

[cgrey8]

It may be cheaper just to use an external fan controller. They aren't but about $150. I bought from from Brian Baskin's company DCC:

Delta Current Control
http://dccontrol.com

I've been using one of his fan controllers in my truck to control my pusher fans since I did the V8 conversion. It's been a solid product and is fully variable speed, not bang-bang operation the way single/multi-speed fan controllers are. Supposedly, that helps with the life of the fan motors. The one thing I tend to disagree with is that these are not so much current controlling devices as they are frequency driven devices. They seem to pulse 12v to the fans at varying frequency and pulse-widths based on the temperature sensed from the sensor you locate in your radiator.

I applaud your effort to want to find a replacement solution for that missing IC. I'm just not sure it is worth the effort vs spending $150 on a superior solution. However if this is purely a project to do just to see if you can, then that's different...carry on.

[d347643]

Same freq but pulse width varies. It doesn't control current but the fan speed. By driving the load with a pulse train of the appropriate duty cycle, the load will turn at the resulting average. That's why you get half speed at 50% duty cycle. Additionally, correct use of PWM all but eliminates inrush current spiking..

Drew

[decipha]

anyone ever compared an 89-90 GURE supercoupe ecu against a guf to see the differences?

since a gufb tune can be ran on a GURE ecu then the hardware has to be close enough to be copied

maybe even run an 8 from the 6 ecu ?

the supercoupe ecu has an upshift lamp as well as a knock sensor too

[vristang]

anyone ever compared an 89-90 GURE supercoupe ecu against a guf to see the differences?

since a gufb tune can be ran on a GURE ecu then the hardware has to be close enough to be copied

maybe even run an 8 from the 6 ecu ?

the supercoupe ecu has an upshift lamp as well as a knock sensor too

You talking pics of the internals?
I have an X3Z I could crack open if it would help... not sure that's what you're getting at though...

Maybe just a pic of a GURE would be enough for one of these electronics guys to see if the hardware is there?

[cgrey8]

There is a pic of a GURE EEC around here somewhere. I think it was Frit that posted it, but I can't remember for sure. In that pic, you could clearly see the chip stuffing of additional components that didn't exist on a GUF1/A9P. In fact the circuitboards look nearly identical with components and pads for components, the only difference is the GUF1/A9P had components missing for pad locations the GURE EEC had stuffed.

[decipha]

I got a gure guess I could try 1 day if I get drunk enough

[xd41efisc]

Try this for pics.
viewtopic.php?f=2&t=17455

[Pontisteve]

Back from the dead, I know, I know...

But I was wondering if there was ever consensus on how to control fans with the stock A9L/A9P computers. Do you have to run a small relay to a large relay every time? Can I just run a standard Bosch 30/40 amp relay and directly control the control side ground with an A9 computer? Or do I have to run a small relay to control the normal size relay?

Did we ever figure out what pins control the low fan and what controls the hi fan? Or is the pin 41 hi fan the only one that's there?

By "not enough ground", can I assume that means the transistor inside the PCM is not able to pass the current that a relay needs to ground the control side of the relay? Relays take so little to ground them...

[phutch11]

When I was setting this up for my car (CBAZA) I used the instructions from Deciphas webpage (EFIdynotuning) and it worked great. I used the single, high speed wiring diagram and there were literally zero issues. Basically you have the EEC actuate a std Bosch relay and then let the relay kick on the fan.

From the webpage, it seems that this shouldn't be an issue for a GUFx box, but I don't personally know.

Good luck

[decipha]

low spd output hardware is missing if u want it youll have to steal the hardware from a GURE ecu

[Pontisteve]

But the high speed fan output controls exist in all the EEC-IV PCM's on pin 41? We could just ignore the low speed stuff, and use the high speed transistor to control a single electric fan then. If the car has two fans, we could just use the output from fan relay #1 to trigger the control side of fan relay #2. That way there wouldn't be twice as much current thru the PCM transistor.

It sure seems odd to me that if the hardware exists, the transistor wouldn't be able to control a single Bosch 30/40 amp relay. I'm going to guess that the people who need to wire up a 3 amp relay to control the larger relay are doing so because the larger relay is a 50+ amp version that requires more current to close the contacts.

Do we know if all EEC-IV PCMs have this high speed driver? Or which PCMs have which drivers? What about the automatic A9P type computers?

[Shaker666]

I've never seen so much uncertainty over EEC fan control! Granted, I had issues wiring my EEC-V high and low speed fan controls up, but I got it working properly in the end. Now I want to do the same for the EEC-IV in my Mustang, but confronted with the issues surrounding pin 55. Pin 41 (HEDF) is a no brainer, just look at Mike's reference page and you're good. I heard that remanufactured EEC-IV units have the fan control hardware for both HEDF and low speed EDF. Anyone concur with that theory?

[xd41efisc]

O.K. I did a bit of playing around with this again today, I had compared GUFB and GURE EECs before to see what was missing for the fan control.
Today I got around to unsoldering (pain in ass but doable) a 71001FB chip from an old XF Falcon 6AA EEC i had lying around.
I then sucked the solder out of the A9L EEC where the low speed fan chip locates, and then soldered the 71001FB that I pulled from the old EEC into the A9L.

I also soldered a 1000pF capacitor as shown in an EEC schematic I found on the web a while ago.
This capacitor on a GURE EEC is a small yellow coloured SMD just below the main connector, it has a track leading to pin 55 and the other end is grounded to the case via another track that also grounds pin 36 (spout pin).
I had capacitors in the 6AA EEC but could not tell if the were 1000pF, so I went to the local Jaycar (electronics shop in OZ) and got a few normal ceramic type 1000pF capacitors, turns out they are labeled 102K, and the 6AA EEC had loads of these in it, I didn't want to take a chance that 102K on the 6AA was something else.
I soldered this to the A9L board where the SMD type would normally go.

I then burnt an A9L tune with both EDFHP and HEDFHP enabled, and set the temps low enough that the fans would come on and off without getting things to hot.
I put the chip onto the modified A9L, fitted it to the car and turned on the ignition and the low speed fan came straight away, I started the engine and the fan stayed on.
I the switched the A/C On to see what would happen and the A/C compressor came on and Low fan turned off. (at least the EEC is controlling the low fan).
It looks like the EEC grounds the low fan relay to turn the fan off, I changed the wire going into pin 87 on the relay into pin 87a and the low fan works as intended, until I shut the car off, then the fan started.
This is because my relay gets its 12v+ from the battery not a switched ignition wire, the EEC grounds pin 55 when it is off, I will change the relay feed and it will work fine.

So at this point it looks like all you need to do is add the 71001FB chip to get low fan control on a GUFB EEC, I say only the 71001FB at a minimum as I removed the 1000pF capacitor to see what would happen, and it worked the same as with it, I put it back on because it is probably a noise filter for pin 55 from the relays back EMF or something like that.

Bottom line is A9L pin 55 Low speed fan control can be done, I just need to check the interaction between High and Low speed, I need to change my wiring a little.

I will keep you posted.
Chris. (xd41efisc).

[xd41efisc]

Also does anyone have a schematic of the fan control on a GURE equipped Thunderbird.

Thanks.

[85GT]

Picked a GURE about a year ago to do just the same. Just haven't found the time.
Got pics?

[xd41efisc]

Just finished checking if this works properly, and it does.
I took a few photos just need to load them on here some how.

The wiring for the relays is a bit of a pain, I need 4 relays to get it to work the way Ford set the fans up over here (on EL/XH Falcons).
They use 2 fans and run them in series for Low speed and in Parallel for High speed, from what I can tell from the web the US stuff has a single fan with high and low windings in them.
Ford use 2 normal relays and 1 change over relay to achieve this, using any EL/XH Falcon EEC (V8 and I6 operate the same).
I have had to use 2 normal and 2 change over relays to get the same result with the A9L.
I presume with the single fans you guys have you will probably need to use 3 relays, or the CCRM box or whatever it is called.
The CCRM Box was used on GURE (as far as I can tell) so it will most likely work on the A9L as well.

The problem is the EEC pulls the low speed relay to ground to turn the fan off, this is opposite to the EL/XH EECs.
I had to change the low speed relay to a change over type and move the supply wire to pin 87a on the relay, every thing works fine until you turn the ignition off (EEC loses control of pin 55), then the low fan speed kicks in.

To stop this I have added relay to shut power off to the contacts of the low speed relay when the ignition is off, the coil of this is fed from the same supply that turns on the Main EEC relay with the ignition.
When you turn the ignition on this relay kicks in and lets power go to the low speed relay contacts, at the same time the EEC is powered up and grounds pin 55, and opens the contact to the low speed fan, until you turn the A/C on or the temp reaches the point you have set it to, the EEC then looses the ground to pin 55 and drops power to the low speed relay in turn closing the contact and turning the low speed fan on.

The high speed still work as it would from the factory, and so does the original change over relay, both these relays are grounded through pin 41 to turn them on.

I have a wiring diagram of this I will scan it and post it up, when I post up the photos.

[xd41efisc]

This is the photo of the Chip and Capacitor you need to add for the low speed fan control.
Both circled, Capacitor is to the left bottom to the right of the main connector.

A9L Fan Chip2.jpg (417.23 KiB) Viewed 44440 times