[85GT]

Cool, thanks for the pic and research. For some reason, I was thinking there was a clamping diode for back emf from the relay coil.

BTW, 102K is standard labeling for capacitors. Its translates into 10 plus 2 zeros picofarads.

[sailorbob]

Nice work :)

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.

Yes, you should keep the capacitor.

You should also have a Zener diode connecting the two clamp lines (pins 2 and 7) to ground. Probably the same type as fitted either side of the 71001FB you installed (if they are the same otherwise the same as the one between the two quad driver chips). The mounting position appears to already be there.

The Texas Instruments DS3658 Quad High Current Peripheral Driver may be a compatible replacement for the 71001FB.

[harold]

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

I was trying to figure out a clean way to do that. I'm looking forward to seeing your diagram. I just dropped it since I was going to swap to an EEC-V this winter anyway.

[xd41efisc]

Dereck I had a bit more of a look after you mentioned the diode, and it probably should have it, also there is a capacitor on the back of the board that wont hurt to be fitted as well.
It looks like the main purpose for this chip is for the Cruise control on the GUREs, but it also does the low fan control.
Below is a list of what pins on the chip go where.

PIN 1 on the chip goes to some resistors to the right of it, these then go to some transistors and other stuff, and end up at EEC PIN 11, that is for a speed control solenoid + (cruise control?).

PIN 2 links to PIN 7 and to the diode you mentioned, the other side of the diode goes to POWER ground.

PIN 3 goes to EEC PIN 35 speed control vent solenoid, its also connected to a resistor array.

PIN 4,5,12,13 are linked together and go to power ground, PIN 4 also has a spot for a capacitor that is also connected to PIN 11 on the chip, PIN 11 I think is a power supply to the chip, so this capacitor should be added as a filter.

PIN 6 goes to EEC PIN 51 speed control vacuum solenoid, it is also connected to the same resistor array as above.

PIN 7 links to PIN 2 as above.

PIN 8 goes to EEC PIN 55 and is the low speed fan output, it is also connected to the resistor array as above.

PIN 9 goes through some resistors and stuff and ends up at a CPU PIN.

PIN 10 goes direct to the CPU.

PIN 11 goes to capacitor that goes to PIN 4, and also picks the power supply.

PIN 12,13 are linked and connected as above to PINS 4,5.

PIN 14 goes to PIN 14 on the chip below it, I am not sure what this does.

PINS 15,16 are linked and go direct to the CPU.

So it looks like most of the chip is for cruise control.
I have found some stuff out about the shift indicator light and a few other things as well, but I will leave it at that for now.

[sailorbob]

Are those pinouts from a GURE ecu?

[xd41efisc]

Yeah mate they are from a GURE EEC, I had a GURE (C0S) and GUFB (A9L) side by side when I compared them, I have a bit more to add about a few other thing missing from the GUFBs, but the above is what is related to the chip.
I spent about 4 hours tracing all the connections to that chip, but found a few other thing along the way.
I will post it up when a bit later.

[sailorbob]

Pinouts:

1 - out A
2 - clamp 1
3 - out B
4 - gnd
5 - gnd
6 - out C
7 - clamp 2
8 - out D
9 - in D
10 - in C
11 - +5 Vcc
12 - gnd
13 - gnd
14 - enable
15 - in B
16 - in A

Yes, if there is meant to be a capacitor between Vcc (pin 11) and gnd (pin 4) then add it.

Early ecu's didn't have the capacitor on the clamp lines diode but it seems to appear on the later ones. No idea why pins 15 and 16 would be linked.

[RJCarp2]

I know I'm bringing up an old thread (again), but there's a question in here that went unanswered and I have the same question. Will the fans run with key on, engine off if the ECT value is above the fan setpoint? I'd like to put in a fan setpoint value lower than room temperature in my garage to confirm I have everything correct.

Thanks,
Rich

[xd41efisc]

Its been 7 months since I did the chip install and it is still going good.

I was trying to figure out a clean way to do that. I'm looking forward to seeing your diagram. I just dropped it since I was going to swap to an EEC-V this winter anyway.

Below is the diagram I used, it works like this:
The fans are connected in series for low speed, or parallel for high speed.
PIN 55 goes to ground to turn fans OFF.
pin 41 goes to ground to turn fans ON to HIGH.
R2 and R3 are change over type relays, R1 and R4 are standard type relays.

R1 turns on power for slow fan speed when the ignition is turned on, they do not come on (except for a second before EEC powers up) because R2 is
powered by pin 55 going to ground and keeping slow fan speed OFF.

When slow speed temp is reached EEC will loose ground on Pin 55 and drop power to R2, in turn closing the 30/87a contact on R2, and turning both fans on SLOW.

When high speed temp is reached Pin 41 goes to ground and R3 and R4 are powered up, this does 2 things R3 changes from the 30/87a contact to 30/87 taking both fans out of series and putting 12v+ direct to fan 2, (fan 2 is always earthed) and R4 energises closing the 30/87 contacts to provide the earth for fan 1.
Pin 55 remains as it was for low speed (no ground), this keeps 12v+ on fan 1.

R1 is needed to stop fans coming on when EEC is not powered.

A9LFANS.jpg (81.7 KiB) Viewed 33106 times

[Shaker666]

Got some useful information!

I happened to have a D9E2 catch code, speed density EEC-IV out of an '89 Bronco laying around. I cracked it open and you know what I found? Not one, but two 7F001FB chips inside! Might be an easy source to find these chips if retrofitting for dual electric fan control is a priority for your DIY project.

[Shaker666]

Also, would someone be able to post pics of their modified A9L PCB, please? Aside from the chip, I'm unsure of what else is needed and where it needs to be added on the PCB.

[XantheFIN]

Search this guy:
http://ford-club.org.ua/board/index.php ... pic=101434
http://www.souleyman.ru/forum/viewtopic ... 2&start=20


He has done some very nice work. Maybe he is already got some Sierra or Granada EEC-IV ecu which holds this Fan controller too.. never know.. some has two MAFs and knock controller.

???

[Shaker666]

I ordered a couple of TI DS3658 chips and will see how it goes when I solder them in place.

[Shaker666]

I've got 5 of these DS3658 chips, but was curious whether pin 55 on the EEC-IV connector is open without one of these chips installed. Does anyone know?

[Shaker666]

FYI, we got this mod working successfully using the new DS3658N chips in conjunction with a TIP31 transistor to invert the output, last night. Need to 3D print an enclosure for the small PCB we smashed together and probably pot it somehow since my 1st use case is in a 4x4 that literally wades through streams on a regular basis.

[Pontisteve]

I would love to see a picture of what you did. Are you saying you used a modern version of the original 71001FB chip, and soldered it onto the board in the original location? Or did something remote?

Was it just as easy as soldering on the 2nd chip, or were there other things that you had to add?

[Pontisteve]

Is this the chip for the fan?

http://www.ebay.com/itm/71001FB-SemiCon ... SwHxVW8AvP

[Pontisteve]

Does anybody have a datasheet for the 71001FB fan chip? I'm curious to know exactly how much current the chip is rated at.

Also, for those of you who mentioned 1 amp max current, where did you come up with that number? And is the chip current limited for protection, or will you fry it if you try to pass more current thru it than it's designed for?

[mustangdriver]

Hello and sorry for bringing up the old thread again.
It's nice that it's being discussed here, I thought I was the only one looking for the ICs.
I also bought 5 of them - from Aliexpress, you can get electronics there for a low price, if it breaks you don't have to worry...
Cost: €8.33 - all inclusive tax, shipping. I put the circuits in storage in case a 71001FB burns out in the EEC.
Datasheet is attached.

DS3658.pdf

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IMG_20240919_221157.jpg (99.04 KiB) Viewed 4244 times

[Pontisteve]

Hello and sorry for bringing up the old thread again.
It's nice that it's being discussed here, I thought I was the only one looking for the ICs.
I also bought 5 of them - from Aliexpress, you can get electronics there for a low price, if it breaks you don't have to worry...
Cost: €8.33 - all inclusive tax, shipping. I put the circuits in storage in case a 71001FB burns out in the EEC.
Datasheet is attached.
DS3658.pdfIMG_20240919_221157.jpg

Ooh, that's great info! How did you figure out that this IC would be compatible? Would you mind sending me a PM or email to pontisteve@earthlink.net? I want to run an idea by you.