Page 1 of 1

2009 CTS-V 160 deg thermostat and fan settings

Posted: Wed Oct 31, 2012 7:33 pm
by wetcoast
Hi all,
I was just wondering if anyone had experimented with adjusting the fan settings to suit a 160 deg thermostat? I want to set them with my Diablosport Trinity but want to go ahead educated first.

TIA,
Chris

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Wed Oct 31, 2012 8:39 pm
by Mike_Levy
They told me how to do it in an older post. Never got a chance to try it before the car was traded in. I hate the way GM controls the fans. You have to set a percentage of the maximum speed. With Mopar it was so easy; set the turn on temps for low, medium and high speeds and that was it.

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Thu Nov 01, 2012 11:55 am
by wetcoast
I agree. It does seem like a lot of settings to accomplish a lower fan temp control.

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Fri Nov 02, 2012 12:15 pm
by wetcoast
Ok so I started to put some more time into figuring this out.

I plotted the stock engine temperature vs. fan power settings in an excel chart and then extrapolates a temperature shift for the popular 160F stat.

The stock thermostat is 194F and the common replacement is 160F thus a 34F shift cooler.
Fan vs. Temp Chart sm.png
Fan vs. Temp Chart sm.png (52.7 KiB) Viewed 4064 times
The problem that I see is that the lowest temperature that we can adjust the fans to turn on is 192F. Per the chart this would mean that the fans would have to start at 87.78% fan power.

My request would be, if possible, to add at least 6-9 more temperature setting points below 192F.

In my opinion anything less would make the adjustment settings in the Trinity very limited if not useless.

Mike et al, Can it be done?

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Mon Nov 05, 2012 1:12 pm
by mikel
problem is, the factory PCM only has the cells present down to 192*....not much more that can be done there...

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Mon Nov 05, 2012 2:35 pm
by wetcoast
Jesse on Cadillac Forums indicated that the entire map had to be re-flashed to map below 192F. I gather that's more that you guys want to do..... it would sure be nice if the adjustment option you're selling had a functional use.....

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Mon Nov 05, 2012 2:39 pm
by Mike_Levy
Thats not an option with a tuner like this. To reflash it like that, they really need the computer in front of them, which many people don't want to do, hence the functionality of the tuner.

Re: 2009 CTS-V 160 deg thermostat and fan settings

Posted: Mon Nov 05, 2012 4:23 pm
by mikel
wetcoast wrote:Jesse on Cadillac Forums indicated that the entire map had to be re-flashed to map below 192F. I gather that's more that you guys want to do..... it would sure be nice if the adjustment option you're selling had a functional use.....
to do so requires a custom operating system, since your doing something beyond what they designed into the pcm code. We are not big into rewriting the operating system when GM did a pretty good job to start :)