what controls the drivers cooling fan? Where in tunerpro is the adjustment for it? My drivers cooling fan is always running from startup to shut down.

I even tried unpluging the fan temp switch in the passanger head but it still runs.

what would I adjust or turn off to make it come on when it gets to a certain temp?

thanks

 

i know when you ground the ALDL ports to check engine codes, that fan should come on.

i dont think you can control it in tunerpro at all. its run on a relay and the head switch from what i've read here.

For some reason tho, i think when i ran a stock ARAP bin in my car that fan was on the whole time, but when i run the stock AUJL bin, its off? i cant remember if thats what happend or not

 

well last year when I first cranked up my motor I used the stock chip and then fan didnt run...it would come on like normal when the temp got up, with my mail order tune the fan is always on. So something in there controls it. right? Im just curious cause it cant be good to run all the time.

 

"i dont think you can control it in tunerpro at all."
The 6E expanded has the fan control in the contants; can set on / off temps there.

" its run on a relay and the head switch from what i've read here."
Does your car have ECM control off the fan?
If not then you have a fault with your fan wiring

"I even tried unpluging the fan temp switch in the passanger head but it still runs. "
Check relay, may be stuck in closed position

 

i can control the one fan with the computer...fan 1 which is passenger side. i see no controls for any other fan.

 

Same as some of the C4 Vettes; main fan by ECM ,second fan if fitted direct of a sensor in the head.

 

yes, so if its controlled by the sensor in the head, then there is no way to control it in the ecm correct?

so if its on for some reason when it shouldnt be on, then something is wrong in the wiring?

 

Sounds to me like something isn't right with your mail order memcal. I would start by verifing that your check engine light is functioning. At key on the light should flash once then stay on until you start the engine. On my 88 the driver side fan is the one controlled by the computer and the passanger side is controlled by the switch in the head. If your using the xdf file that Mark supplies with TunerPro there should be 4 constants that control the fan. They're labeled fan 1 on and off AC on and off. I never actually adjusted the fan settings on mine since i recently converted to the 730 ecm.

 

I've had GM fans come on with no freon in the a/c system by just switching the heater controls to any A/C settings. Is your A/C selector in the on position when the fan is constantly running. Maybe just a shorted A/C pressure sensor is grounding the relays circuit.

 

Yes, most likely that's it, but there's a total of 3 circuits in parallel withh the relay coil:
ECM; passive input, monitors fan activity
High temp switch in head
A/C pressure switch
one or more has find it way to ground.

 

There is a switch in the bin for normally open cooling fan request.

;LC017: FCB $28 ; %0010 1000, 4th AIr Flow Mode Word
;
; Bit 0 = Use LD VAL FOR BLM NOT DISPFLOW
; 1 =
; 2 = 4th GEAR HWY MODE SPARK ADV ON
; 3 = If CCP CHG, FORCE INT TO 128
;
; 4 = TCC LK'ED HWY MODE SPARK CK ON.
; 5 = N.O. COOLING FAN REQ INPUT
; 6 = Use PWR STEER PRESSURE SW
; 7 = Use TCC OUT TO CNT'L A/C CLUTCH
;---------------------------------------

For corvettes, this switch is normally not set. You may want to verify that this switch setting is correct for your fan hardware.

 

My SES works like it should. I dont have AC anymore and removed everything out of the bay that deals with AC. I have the passenger fan hooked up to a toggle switch in the car and can turn it on when I want. THe drivers side fan is always running. Like I said if I put the stock chip in the fan does not run at startup but the car does not ilde or run good either I have to keep my foot on the gas cause of the 305 chip trying to run the 385

 

do you have tunerpro and a chip burner/reader to look at both bins?

i have to look in there to see if there is a option somewhere.

 

I dont have a way to read the stock chip only the mail order

 

I think you'll find the answer to your problem in Tequilaboy's post.

 

Then just run a independent wire from the thermal switch to the green wire on the relay and that will eliminate the ecms control to turn the fan on.

 

If you can read the MailOrder chip look in the "Flags/switches" section for "Cooling Fan N/O Req. Input". Click on it. If it is checked when it should not be checked or not checked when it should be it will cause the fan to stay on. If I remember correctly it should be checked. If you do not have the stuff to reburn a chip then you will have to try another little trick. Let me know what you find and I will try to help you with that trick. But Please, whatever you do, DO NOT START ADDING WIRES that you don't need. toggle switches and wire splicing are for those who can not/will not figure out how to do it the right way.

 

i think i have a copy of your chip, believe you sent it to me awhile back to look at the spark tables or something

anyway i looked at it and it says Cooling Fan N/O Req. Input is set. maybe it should be Not Set?

 

right, I just checked it and the "cooling fan N/O reg input" is CHECKED to SET

 

Just wanted to give a heads up. I "unchecked" the flag and that does control the fan. THe fan now does not run all the time. Also my passenger fan works like it did, I can turn it on/off with the flip of the toggle in the car weather Fan 1 is running or not.

Fan 1 driverside comes on and goes off when gets to a certain temp but I was not monitoring when I checked it. SO i dont know the exact temp this occurs.

In the chip "fan 1 turn ON (A/C OFF) is set to 203*
"fan 1 turn OFF (A/C OFF) is set to 193.55*

are those comfortable degree's

 

Me and my friend have a strange problem on our necks..
He have an 1989 Camaro that we have chippet little bit because he changed is cam and so on... (not important in this question )

We changed from APYN $6E to ARAP instead, because ARAP did have a better affect on the car, We didnt use the ARAP SA we used the stock SA and adjusted it...

Now to the problem, He have removed the AC and installed an regular blower, now when he starts the car the fan runs all the time... Ive burned different chips with the Coolant fan N/O req CHECKED / NOT CHECKED, the fan runs anyway, I think that it is the left fan (not 100% sure at the moment but I think so)

If he removes the moates adapter and using the stock MEMCAL the fan dosent run. We havent changed the PROM since the AC removal so its installed correctly and the car runs really good with the custom prom its just that the fan is constantly running... what else could cause this problem ?!

The fan stops running when using the stock MEMCAL/PROM and when putting in the custom it starts....

This problem didnt exist while the AC was installed....

please help me out with this. Just made an new PROM to send him and try to see if the fans runs, he will just test it to see if it starts or not...

 

Anyone that could give an guess or answer on this ?!

 

What did he do with the A/C pressure switch?

/N.

 

Really dont know right now, could call him and ask him, But why is it working with the stock memcal ?

It it be a wiring problem ?! shouldnt it be the same in the stock prom then ?!
Wanna know before I send more proms.

 

Its the leftfan from inside, the driverside fan that runs all the time.

And the AC is removed, all connectors and everything is just unplugged and taped toghether so they dont make contact to anything..

So thats what done. And as said the dirverside fan runs all the time with the custom PROM, when stock memcal is installed its stops.

 

What I learned
Primary fan-controlled by chip setting/AC on-pressure switch.

Secondary fan-Head sensor input/AC on pressure switch.

Primary fan input req box checked.
Would work backwards if not checked ( Fan on until temp
came up)

If not running AC and high pressure switch somehow
grounding, fan should not come on unless turned on
in car.
Running 165-6Exfd.
Just a few thoughts
Now trying to figure out how to get both fans ECM controlled.

Later

 

Maybe you could use the EGR or AIR output to control the second fan, if you have deleted one of those I think that have been up in another thread here, try to search.

Otherwise you could put a jumper wire in and maybe a xtra relay to let both fans come on at the same temp.

On my ECM -730 or -749 (switch sometimes to check things ) with $58 code I use the EGR output to control my CCP and it works good.

/N.

 

There was a thread about a year ago been trying
to find on that, and had it set up just that way.
Will keep looking.
Amp draw would be the only problem and I guess
a separate relay would handle that.
When it comes to electrical I'm more of a show me
don't tell me.

Later

 

Yeah but the driverside fan always runs, cannot be shutoff.
Its only off when using the stock memcal, but the strange thing is that
the driverside fan did run with and without the N/O checked.
Also we tried another prom, same thing, will send 2 new proms to
see if the fan stop running..

 

Have you tried to burn a stock chip and placed it on the adapter?

 

Yes did try that, the same thing, Fan did run anyway with and without the N/O checked..

The only thing is that I dont know 100% sure that it is the stock prom because its downloaded so someone could have changed something and uploaded it as the same name... One thing todo is to scan the stock memcal, but then the car is useless for some days before he get it back... then we know for sure that it is a completely stock prom... thats the last way out.
Sending 2 new proms that I know is stock from another car that I borrowed and scanned... will see if that helps..

 

Memcal not mounted correct on adapter, or some solder/wire on adapter broken.

 

But why have it been working good until the AC was removed ?!
The car runs really good even with the fan running and there are no SES light or codes..

 

So

Stock memcal in ECM -> FANS OK
Stock memcal on adapter and stock burned chip on adapter -> FAN NOK

--> Something wrong with adapter or the burned chip.

*The adapter doesnt do anything its only an extension of the memcal and allows you to replace the PROM with another one without soldering.

Good luck

 

Yeah but why did it work fine when the AC was connected ?!
The problem came when the AC was removed.
Maybe ill send a new adapter to test to see. but that 4burned proms should be bad is unlikely.. Sending 2 new today also. Will call and see how it looks today.

 

Now I have tested the adapter and the ARAP6 code in my car.
The fan didnt turn on, So im sending a new adapter and some proms to test.

If it dont work now, then whats the problem ?!
If it works on my car, then it cannot be the adapter or the prom.

 

If it doesnt work with the one you have tested on your car it has something to do with the AC removal, there are 2 wires to ECM from AC stuff, but since its working with stock memcal I dont think so.

Then there is a possibility that the memcal isnt placed correct on adapter.
Have never tested to put it wrong so I dont know how it will affect SES or drivavility.

 

Ignition ON (engine off) : Driverside FAN does NOT run.

So then its not the adapter thats the problem, if so, the fan would run when engine is off and ignition is ON, Thats not the case


The driverside fan starts to run when the engine starts and runs all the time the engine is running, stops when engine is killed / showdown. And stays off if the Ignition is set to ON (engine off)...

The fan only runs when the engine is running...

Just mailed 4 prom thats tested on my car and a new adapter, just to try.
If the problem still occours then there is something else thats wrong right..

 

With regard to Theking's problem: I had the same problem; took out the A/C and fan would be on all the time that the engine was running. I have all stock computer and chip and mine is an '85. To fix it I attached one of the sensors from the A/C. It was the one in the small hard line that comes out of the bottom of the evaporator. I think this is what the wiring diagram in my Haynes manual refers to as the "Fan A/C Pressure Switch." Anyway, I measured the resistance of the sensor and got 0 ohms, so I took a small piece of wire and stuck it in each terminal on the connector and started the car. And, no fan on startup. One thing I should mention: I did not run the car all the way up to fan on temperature (didn't want to get it to hot, had some other stuff to do under the hood)... I don't really think there would be a problem, but it wouldn't hurt to make sure that the fan turns on on its own at the proper temp.

So, that was my solution for that. One other wierd thing: When I took the A/C out of my '89 IROC with dual fans, I did not have this problem at all. Driver's side fan maintained normal functionality...

Anyway, hope that helps. Or, at least provides something else to think about...