Question for Subaru veteran repair and ecu guys:radiator fans

[Huehuecoyotl]

what triggers the OE rad fans?
I see two when I look down appear to be wired in parallel?

is there a temp sensor somewhere?
can its settings be dialed/can it be replaced?

is it just AC?
is it water temps?
does it care about cyl head temps and stuff like that too?

do high oil temps have any effect?
if someone can explain all applicable fan logic, thats what i wanna know

lastly @Visconti and @PERRIN is there anything in ecutek that can allow a tuner to change how often, when how long etc these fans come on? at what temp?

I have something I'm tossing around as far as ideas on a 3.5A oil cooler fan thats triggers whenever water temps rise enough to trigger the fans so thats why I am asking
any reason I would be worried about addinng a small additional load? I was gonna bump up the fuse-havent even checked, is there one? can add relay, but such a small load

Thanks in advance!

[Ranatsu]

One is triggered with the AC the other is triggered based on coolant temp.

Pro tip, you can put the car in the on position but not running, turn the AC on and the fan will run

[Huehuecoyotl]

Originally Posted by Ranatsu

One is triggered with the AC the other is triggered based on coolant temp.

Pro tip, you can put the car in the on position but not running, turn the AC on and the fan will run

So I see that both fans come on whenever the AC is on, car on or off
when the car is on they both cycle when the car is off they both stay ON in the On position

Which fan comes on based on coolant temp? This is important!
thanks

[Visconti]

Originally Posted by Huehuecoyotl

what triggers the OE rad fans?
I see two when I look down appear to be wired in parallel?

is there a temp sensor somewhere?
can its settings be dialed/can it be replaced?

is it just AC?
is it water temps?
does it care about cyl head temps and stuff like that too?

do high oil temps have any effect?
if someone can explain all applicable fan logic, thats what i wanna know

lastly @Visconti and @PERRIN is there anything in ecutek that can allow a tuner to change how often, when how long etc these fans come on? at what temp?

I have something I'm tossing around as far as ideas on a 3.5A oil cooler fan thats triggers whenever water temps rise enough to trigger the fans so thats why I am asking
any reason I would be worried about addinng a small additional load? I was gonna bump up the fuse-havent even checked, is there one? can add relay, but such a small load

Thanks in advance!

We have a bunch of different fan control settings

[Huehuecoyotl]

Originally Posted by Visconti

We have a bunch of different fan control settings

what are they?
can you toggle values from on to off in the chart below?
if so I need some help

[Huehuecoyotl]

No one knows anything on modding this?

[Visconti]

Originally Posted by Huehuecoyotl

what are they?
can you toggle values from on to off in the chart below?
if so I need some help

A little more advanced but yes

[Huehuecoyotl]

Originally Posted by Visconti

A little more advanced but yes

Really @Visconti?

So I'm honored that you post twice,post me some info you can actually share, man!!

(... or are you just having fun playing 'hold out' with me )

What do you use is my question to toggle those values? of affect how often they come on, or how hot it runs overall? its not running hot, I'm just wanting to prevent that

It aint ecutek...based on the response I got from them, see attached pic of my emailed response from them

I am planning on running a relay and (scroll to bottom of page!)fan off the factory fans that cools my oil cooler anytime water temps rise, as usually the two will rise together. PHX is a animal of its own for those who track

I updated my thread with the new fan I added, so really John, any help you can offer is welcome! Thanks in advance. Lookin fwd to working with you on flex fuel too, my kit will be at 12psi by then.

[Calum]

Try a vw fan switch from the early 80s.

[HRTROB]

Reviving an old thread

Do your fans intermittently switch to high speed when the AC is on? I don't remember the fans being loud at all when I was NA with the stock tune.

I installed a supercharger, had my ECU flashed with an Ecutek tune, and now the fans cycle from low to high speed intermittently whenever the AC is on. Even if the coolant temps are around 88-89C. With the AC off, the fans turn on and run at low speed when coolant temp reaches 92C and then turns off when the temp goes down.

I then upgraded my radiator to a Koyo unit, same thing. The fans still cycle from low to high speed even with normal coolant and oil temps (I have an oil cooler installed).

How is the high fan speed triggered in the stock ECU? I'm thinking that maybe my tuner modified the fan logic in my tune. Or maybe the fans were always like that and I just couldn't remember?

[Calum]

Originally Posted by HRTROB

Reviving an old thread

Do your fans intermittently switch to high speed when the AC is on? I don't remember the fans being loud at all when I was NA with the stock tune.

I installed a supercharger, had my ECU flashed with an Ecutek tune, and now the fans cycle from low to high speed intermittently whenever the AC is on. Even if the coolant temps are around 88-89C. With the AC off, the fans turn on and run at low speed when coolant temp reaches 92C and then turns off when the temp goes down.

I then upgraded my radiator to a Koyo unit, same thing. The fans still cycle from low to high speed even with normal coolant and oil temps (I have an oil cooler installed).

How is the high fan speed triggered in the stock ECU? I'm thinking that maybe my tuner modified the fan logic in my tune. Or maybe the fans were always like that and I just couldn't remember?

The fan is cooling the AC condenser.

[HRTROB]

Originally Posted by Calum

The fan is cooling the AC condenser.

Thanks for the info! This is also what my tuner told me, I just wanted to confirm. Makes sense since I noticed that the fans go to high speed even if the coolant hasn't reached normal operating temperature as long as the AC is on.