Electric Fan troubleshoot

[revskus]

We installed a LS3 crate swap in a C10 pick-up with electric dual fans vintage air Speartech harness & ECM programmed also by them for the initial startup. Before the truck was sent to Dyno tune the fans kicked in at 190deg & kicked out around 175deg as I think they should. When we picked it up the truck was around 160deg and the fans were on when truck was started. Took truck home parked it in the heated garage, went back the next day started the truck fans came on the engine temp was around 65-70deg. Backed truck out of garage to make space (Its winter here so the truck was outside for a few hours) dropping the engine temp to around 20deg. When started the fans weren't on and stayed off until the 190deg. but never kicked back out again.
I repeated the leaving it outside & it did the exact same thing.
When I talked to the tuner about this they looked at the tune file & say there must be something wrong with the wiring. I looked at the wiring & can't see a problem. It doesn't make sense it was fine before tune.
We tuned the truck using a HP Tuner.
I purchased the MPVI3 it will be here Monday I will look into it myself. Any help on this would be great! What should I look at in the fan settings?
To me it looks like they kick in @ 190deg and will run constant till they get the temp to around 35deg....... Is this possible??

[kevin87turbot]

We installed a LS3 crate swap in a C10 pick-up with electric dual fans vintage air Speartech harness & ECM programmed also by them for the initial startup. Before the truck was sent to Dyno tune the fans kicked in at 190deg & kicked out around 175deg as I think they should. When we picked it up the truck was around 160deg and the fans were on when truck was started. Took truck home parked it in the heated garage, went back the next day started the truck fans came on the engine temp was around 65-70deg. Backed truck out of garage to make space (Its winter here so the truck was outside for a few hours) dropping the engine temp to around 20deg. When started the fans weren't on and stayed off until the 190deg. but never kicked back out again.
I repeated the leaving it outside & it did the exact same thing.
When I talked to the tuner about this they looked at the tune file & say there must be something wrong with the wiring. I looked at the wiring & can't see a problem. It doesn't make sense it was fine before tune.
We tuned the truck using a HP Tuner.
I purchased the MPVI3 it will be here Monday I will look into it myself. Any help on this would be great! What should I look at in the fan settings?
To me it looks like they kick in @ 190deg and will run constant till they get the temp to around 35deg....... Is this possible??

What PCM are you using? Post the tune when you can. We can help you figure it out.

[CranknChrome]

How are the fans tied in with the a/c? The compressor kicks on if the heat is on defrost. So if the fans have a compressor 12v switched relay that could be holding them in. Just a thought.

[TheMechanic]

Check for codes. Some can and will make the fans come on. Do a compare on your original file before it went to the tune shop then use the "View Comparison Log" and you can see exactly what was changed.

[revskus]

Morning
Here is the tune from the truck
It has a E38 ECM and a T42 TCM. thanks guys for looking at it.

[Alvin]

See attached image.

When the vehicle reaches 192 the fan desired goes to 49%.. which is 0-1 fan is on..

when the truck cools below that there is nothing really driving the desired fan lower than 46 which is the conditions to turn the fan off. 1-0

A simple fix would be to put a value lower than 46 in the first cell of ECM 18030

Capture.PNG

[revskus]

See attached image.

When the vehicle reaches 192 the fan desired goes to 49%.. which is 0-1 fan is on..

when the truck cools below that there is nothing really driving the desired fan lower than 46 which is the conditions to turn the fan off. 1-0

A simple fix would be to put a value lower than 46 in the first cell of ECM 18030

Capture.PNG

Ok thanks so changing the "49" value to something like "45" in the cell under 192 is what you mean?
One other question, to do that I will have to purchase credits wont I? I'm very new to HP tuners.

Thanks for you help much appreciated

[Alvin]

I would set it to something very low. Perhaps even zero.

[revskus]

Ok thanks so changing the "49" value to something like "45" in the cell under 192 is what you mean?
One other question, to do that I will have to purchase credits wont I? I'm very new to HP tuners.

Thanks for you help much appreciated

Thanks for the help this worked great.