99 S10 AC Fan issue

[Roundhouseman]

Life is an Enigma, I found a thread that you helped another tuner and I hope you may have an answer. I am retired and live in Tafton PA. I have a 99 S10 with a 04 LM7 5.3l that is wired up like yours and I have the same 6243 PCM and the same operating system 12587603. My fans are wired up individually. It seems once the fan or fans come on, they stay on when the ac is turned off. Attached is my tune file. Any Ideas? Thank you in advance. Steve

[Life is an Enigma]

What radiator are you running with your 5-3 setup? And also do you have a vcm log file you can post? And definitely run the low high setup mimicking the GM factory fan setup both fans running at the same time will definitely help with cooling.

[Roundhouseman]

I have a three row aluminum radiator with two 12? Spal pulling. I don?t have a log yet, I?ll try to get one tomorrow. I?ll rewire the relays next week.

[Roundhouseman]

I did a log file today. It does look like the #1 fan comes on. It did shut off twice. It does seem to take a little while once the AC request is gone. The fan temps seem awful high. Thermostat is the factory recommended. Any advice??

[John5]

I did a log file today. It does look like the #1 fan comes on. It did shut off twice. It does seem to take a little while once the AC request is gone. The fan temps seem awful high. Thermostat is the factory recommended. Any advice??

Hi Roundhouseman,

your on/off settings seems quite high but I guess if your're ok with those temps then fine. You can try removing the enable speed on/off and leave them blank and your run time for fan 2 is set for 3.5 minutes which is a long time but if it's reaching those temps I guess you'd want it to run for a while.