Randy M

I am very new at this so please bear with me. I have modified a $6E and the engine is running good with the initial settings. My problem is I now have the fans start as soon as I start the car and not at the selected coolant temperature (195F on, 185F off, 180F thermostat). I cannot seem to find my problem and it could be that I have looked at the mistake so much I can't see it. Can anyone point me in the right direction?

SMasterson

The 'Normally Open Fan Request' needs to be checked in the bin file. What editing software are you using?

MR. KIDD

I had to uncheck the normally open fan request input in the switch tables this was on a 86vette and a 86 Iroc both work fine now

Randy M

I am using TunerCat to edit the software. If I am reading the responses correctly, I seem to be getting two different answers to this problem. The fans are ECM controlled and not auxillary sensor controlled. The fan relay is wired as normally open and when the engine temperature sensor reaches the selected temperature (195F), the +12VDC on the relay is grounded by the ECM and the fans run. When the fan shutoff temperature is reached (185F), the ground is opened and the fans shut off. All help is appreciated.

MR. KIDD

From what I have seen it seems to vary from one year to another I just had this happen last night to a 86 Iroc I uncheck the box and all is well I also use tunercat.

Grim Reaper

The 6E needs to have the "Normally Open Fan Switch" checked. This is the regular setting for all stock 1989 F-bodies. The ARAP bin does not have this switch checked, and will cause the fans to come on. Checking the box will fix this.

Also, if you accidentally turn on your A/C (including defroster) this will turn on your fans. Also if you have an "error" in your bin - this too will turn on your fans.

Randy M

Thanks everyone. One thing I had done was to check the A/C fan (this particular car utilizes three fans per my mods) and it never ran until the A/C was turned on. I believe the "Normally open fan request" is the problem since this is a '89 F body engine and $6E file. I will make that change and report back.

83 Crossfire TA

iTrader: (2)

Anyone ever figure this out? My ’87 running what started as an ’89 $6e is doing the same thing.

Will either setting for the FAN NO flag eliminate having to ground the AC pressure sensor wire if the AC has been removed?

clippjr8

I had this problem one time and it was too on a 6e, 89 iroc. The problem was a bad bin file. I downloaded another bin and made the same changes and that fixed it. And yes, the NO fan request needs to be checked for the 6e camaros and firebirds. For the vettes it will not be checked.