JEEP SRT 2014 fan setting help required

[Sébast19X]

Hi, I'm wondering how to adjust properly the fan setting on my JEEP SRT 2014 for a 170F thermostat

Fan setting low, med, and Hi vs A/C on and A/C off have clearly no effect.

It's a PWM linear fan and I have only one table to adjust the fan temp vs Ambiant air temp.

Factory setting are something like 215 and 212 vs ambiant air temp

I can put 182 and 180 and the fan seem to cycle on to off correctly, 25-30% DC so he start at around 183F- 184F and stop around 172F to 174F.

If I put value at something lower like 180F- 178F, when the fan start he climb at 50, 60,70, 80 % DC and he never stop !!!

The temperature in my SRT performance screen, and in my dash gauge stop workinig properly, whatever the fan setting I put in the tune. The SRT performance screen seem freezed at 185F, and my HPT log show that the ECT (SAE) have dropped to 169F-170F. I stop the engine for a second, I restart the engine and my gauge and my SRT performance screen, both read the same as my HP tuner ECT (SAE) and the fan are now stopped. As soon as the fan restart the same problems goes on ....

I will post the tune and the log with a short video tonight.

BTW I have the latest HP tuner version downloaded last night 3.2.148 if my memory serve me well.

Best regards,

Sebastien

[Sébast19X]

Log and tune added

[SultanHassanMasTuning]

392 fan setup.JPG


take a look

[Sébast19X]

392 fan setup.JPG


take a look

Ok, but its not what I have in my tune. Mine is PWM linear, not Relay 2 speed.

And this is not the same tabel vs ambiant temp. Take a look, I have put my tune in.

I'm wondering if I'm not fighting air bubble in the systems...

Best regards,

[Hemituna]

Ok, but its not what I have in my tune. Mine is PWM linear, not Relay 2 speed.

And this is not the same tabel vs ambiant temp. Take a look, I have put my tune in.

I'm wondering if I'm not fighting air bubble in the systems...

Best regards,

I chased this one for weeks........and weeks..........
I run 160f thermostats in my SRT's.
There is some logic somewhere in the cars temp gauge system that refuses to allow it to run cooler than 85c desired.
If you set fan at 86c desired, it will cycle nicely between 85c and 89c.
If you set to 85 or less, as soon as that temp is exceeded, the fan will run all day long,
even till the thermo closes and cool water is coming out the rad outlet
I tried all sorts of things, but best fix I have so far is to run 2 ECT sensors.
Extra one goes on cyl head and is wired in parallel with OE.
This reduces resistance and makes the ECT appear to be about 20c hotter than it is.
So now 75c engine temp reads 95c on gauge which keeps fans happy.
Rejig ECT fuel modifiers to suit and all is good!
Fans work perfect and using laser temp gun, engine temps stay in solid 73-78c range.
Cooling system is up to the job too, never gets hot altho fan runs a bit more as you would expect.
Lower ECT does wonders for helping keep knock under control on 6.4's

[06300CSRT8]

I chased this one for weeks........and weeks..........
I run 160f thermostats in my SRT's.
There is some logic somewhere in the cars temp gauge system that refuses to allow it to run cooler than 85c desired.
If you set fan at 86c desired, it will cycle nicely between 85c and 89c.
If you set to 85 or less, as soon as that temp is exceeded, the fan will run all day long,
even till the thermo closes and cool water is coming out the rad outlet
I tried all sorts of things, but best fix I have so far is to run 2 ECT sensors.
Extra one goes on cyl head and is wired in parallel with OE.
This reduces resistance and makes the ECT appear to be about 20c hotter than it is.
So now 75c engine temp reads 95c on gauge which keeps fans happy.
Rejig ECT fuel modifiers to suit and all is good!
Fans work perfect and using laser temp gun, engine temps stay in solid 73-78c range.
Cooling system is up to the job too, never gets hot altho fan runs a bit more as you would expect.
Lower ECT does wonders for helping keep knock under control on 6.4's

Really appreciate everything you are contributing, very good info, this is a very smart idea.

[RedShark_JK]

I chased this one for weeks........and weeks..........
I run 160f thermostats in my SRT's.
There is some logic somewhere in the cars temp gauge system that refuses to allow it to run cooler than 85c desired.
If you set fan at 86c desired, it will cycle nicely between 85c and 89c.
If you set to 85 or less, as soon as that temp is exceeded, the fan will run all day long,
even till the thermo closes and cool water is coming out the rad outlet
I tried all sorts of things, but best fix I have so far is to run 2 ECT sensors.
Extra one goes on cyl head and is wired in parallel with OE.
This reduces resistance and makes the ECT appear to be about 20c hotter than it is.
So now 75c engine temp reads 95c on gauge which keeps fans happy.
Rejig ECT fuel modifiers to suit and all is good!
Fans work perfect and using laser temp gun, engine temps stay in solid 73-78c range.
Cooling system is up to the job too, never gets hot altho fan runs a bit more as you would expect.
Lower ECT does wonders for helping keep knock under control on 6.4's

very interesting,
I noticed my JK with 6.4 conversion not responding to settings i request, i set fan to come on at 90 and many times it still works with engine temp 80
also i noticed the fan is set to work as 3spd relay while its using the JK stock PWM fan

i contacted support and waiting any reply

can it be some limitation with the OS on PCM ?

attached tune file

any help appreciated