99-02 A/C Auto Recirculation Option
03-29-2012, 06:02 AM
#11
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Ok.
Also keep in mind you can't ideally control the fans on a 99-02 based on AC pressure. The best I was able to do was set a fan on delay of 5-10 seconds with an AC request and a minimum fan run time of 45 seconds so if the compressor is cycling its not turning the fans on and off all the time. With the AC on the fans only run on low speed because there is no high pressure trigger telling the PCM to turn them onto high. It can based on engine temp but not AC pressure. FWIW I've never needed anything more than low speed even last summer when it got to 116 degrees one day.
Also keep in mind you can't ideally control the fans on a 99-02 based on AC pressure. The best I was able to do was set a fan on delay of 5-10 seconds with an AC request and a minimum fan run time of 45 seconds so if the compressor is cycling its not turning the fans on and off all the time. With the AC on the fans only run on low speed because there is no high pressure trigger telling the PCM to turn them onto high. It can based on engine temp but not AC pressure. FWIW I've never needed anything more than low speed even last summer when it got to 116 degrees one day.
03-29-2012, 08:27 AM
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Same here,
anytime my AC is on and my Coolant is above 75* my fans come on low.
Ive never had to turn them on high, but i usually will if im stuck in traffic just to be on the safe side.
anytime my AC is on and my Coolant is above 75* my fans come on low.
Ive never had to turn them on high, but i usually will if im stuck in traffic just to be on the safe side.
03-29-2012, 11:00 AM
#13
All of the operating systems with the same OSID are created equal, because they are all the same.
OSID 9381344 used on 1999 & 2000 trucks and cars, 12202088 or 12208322 used on 2001 cars and truck, 12212156 used on 2002 cars and trucks are all the same. That means that I can put a PTO on a Corvette and it will be 100% functional or I could put E fans on a truck and they will work just like an F-body. I see only 25 or 26 fan parameters total for the 512k PCM’s. You just need to tune them to match an F-body
OSID 9381344 used on 1999 & 2000 trucks and cars, 12202088 or 12208322 used on 2001 cars and truck, 12212156 used on 2002 cars and trucks are all the same. That means that I can put a PTO on a Corvette and it will be 100% functional or I could put E fans on a truck and they will work just like an F-body. I see only 25 or 26 fan parameters total for the 512k PCM’s. You just need to tune them to match an F-body
03-29-2012, 11:15 AM
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All of the operating systems with the same OSID are created equal, because they are all the same.
OSID 9381344 used on 1999 & 2000 trucks and cars, 12202088 or 12208322 used on 2001 cars and truck, 12212156 used on 2002 cars and trucks are all the same. That means that I can put a PTO on a Corvette and it will be 100% functional or I could put E fans on a truck and they will work just like an F-body. I see only 25 or 26 fan parameters total for the 512k PCM’s. You just need to tune them to match an F-body
OSID 9381344 used on 1999 & 2000 trucks and cars, 12202088 or 12208322 used on 2001 cars and truck, 12212156 used on 2002 cars and trucks are all the same. That means that I can put a PTO on a Corvette and it will be 100% functional or I could put E fans on a truck and they will work just like an F-body. I see only 25 or 26 fan parameters total for the 512k PCM’s. You just need to tune them to match an F-body
03-29-2012, 06:21 PM
#15
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The 96-2000 GMT400 trucks running the LS1b PCM can have A/C pressure controlled fans with the addition of an F-Body Hi-Pressure switch and the appropriate calibration changes.
Jeff
Jeff
04-02-2012, 07:38 PM
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so what are yall setting in the tune to get the fans to come on low speed with a a/c request? cause at the going rate i am too dumb to figure it out!! HELP PLEASE!
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