1FastBrick
April 13th, 2015, 05:26 AM
I recently installed E-fans On a 99 GMC Sierra, The OS in the truck was 09373372. I activated the fan functions and set the temps accordingly.
When the engine was turned on The fans would come on even at a low temp and run constantly. I did have the correct bi-directional control when commanded Via the scan tool.
I verified the fan settings were correct, Tried another harness, and even programmed a different PCM believing that was the issue. I even tried a different a few different Operating systems. It wasn't until I specifically used a 2002 OS# 12212156 that the fan function's worked correctly.
Some one else did an 2001 silverado around the same time and was having the same issue. I told him about the 2002 OS I used and it worked for him too.
I am being told that when this change is made using Hp Tuners that it function's correctly and you do not need to swap Operating systems to get the fans to function correctly. I have not verified for my self but a reputable tuning company is telling me so as that is what they use to activate fan settings.
I am curious as to what's different in the older OS and why EFI Live could not make the changes to the older OS?
I was running the latest 2015 March update at the time.
My main concern is the Smog inspection as the new program checks what engine calibration the vehicle is using during the scan process as well as the vin#
When the engine was turned on The fans would come on even at a low temp and run constantly. I did have the correct bi-directional control when commanded Via the scan tool.
I verified the fan settings were correct, Tried another harness, and even programmed a different PCM believing that was the issue. I even tried a different a few different Operating systems. It wasn't until I specifically used a 2002 OS# 12212156 that the fan function's worked correctly.
Some one else did an 2001 silverado around the same time and was having the same issue. I told him about the 2002 OS I used and it worked for him too.
I am being told that when this change is made using Hp Tuners that it function's correctly and you do not need to swap Operating systems to get the fans to function correctly. I have not verified for my self but a reputable tuning company is telling me so as that is what they use to activate fan settings.
I am curious as to what's different in the older OS and why EFI Live could not make the changes to the older OS?
I was running the latest 2015 March update at the time.
My main concern is the Smog inspection as the new program checks what engine calibration the vehicle is using during the scan process as well as the vin#