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Fan Controller

Gator48
Explorer
Explorer
On our 2006 Itasca Horizon w/Cummins 400 We had some temp issues out west in June. Warning temps when climbing and I had to downshift to cool things off. Got home cleaned the RAD and all looks good. Issue now is the cooling fan runs all the time on high speed....IF the AC is on. If the AC is off it runs low speed. Doing some research it seems the fan should be off until the engine reaches operating temp. Then low until nearing high temps. Is this correct?
8 REPLIES 8

dons2346
Explorer
Explorer
hostage wrote:
Gator48 wrote:
Thanks all,

That's pretty much what I was thinking. Low fan all the time except for high temps OR AC on.

I was reading on another forum a post from an owner who said "Freightliner said cold engine fan off to normal temp then low to high" mine has never done that.

Guess I am ok....On to Texas later this month.


AC on or off matters not fan runs on low till air and water temps get to max then fans come on to high


Well,I can guarantee you this is not the correct analysis. Ask me how I know.

hostage
Explorer
Explorer
Gator48 wrote:
Thanks all,

That's pretty much what I was thinking. Low fan all the time except for high temps OR AC on.

I was reading on another forum a post from an owner who said "Freightliner said cold engine fan off to normal temp then low to high" mine has never done that.

Guess I am ok....On to Texas later this month.


AC on or off matters not fan runs on low till air and water temps get to max then fans come on to high

Gator48
Explorer
Explorer
Thanks all,

That's pretty much what I was thinking. Low fan all the time except for high temps OR AC on.

I was reading on another forum a post from an owner who said "Freightliner said cold engine fan off to normal temp then low to high" mine has never done that.

Guess I am ok....On to Texas later this month.

doc_brown
Explorer
Explorer
hostage wrote:
imgoin4it wrote:
Not sure but I think the fan runs all the time when the acnd is on. Pretty sure mine does. In fact the engine runs a little cooler when the acnd is on,


R U talking side cooling or rear cooling here?? My 425 ISL side cooling fan works strictly by engine coolant temperature
makes no difference whether AC is on or off


X2 in my 350 ISC.
Steve,Kathy and Josh
Morpheus(Basenji)at Rainbow Bridge
2004 40' TSDP Country Coach Inspire DaVinci
350 Cummins, 3000 Allison
2014 Jeep Wrangler Unlimited Sport S, Air Force One Braking, Blue Ox

SidecarFlip
Explorer III
Explorer III
Time for a fan clutch I believe. The fail-safe mode is 100% engagement.
2015 Backpack SS1500
1997 Ford 7.3 OBS 4x4 CC LB

dons2346
Explorer
Explorer
Gator48 wrote:
On our 2006 Itasca Horizon w/Cummins 400 We had some temp issues out west in June. Warning temps when climbing and I had to downshift to cool things off. Got home cleaned the RAD and all looks good. Issue now is the cooling fan runs all the time on high speed....IF the AC is on. If the AC is off it runs low speed. Doing some research it seems the fan should be off until the engine reaches operating temp. Then low until nearing high temps. Is this correct?


Sounds like your controller is working as it should. The fan does run at low speed all the time and as the temp rises to the danger zone, the fan will speed up. The fan does run faster when the air conditioning is on. Mine runs at a higher speed even when the vent mode is selected.

hostage
Explorer
Explorer
imgoin4it wrote:
Not sure but I think the fan runs all the time when the acnd is on. Pretty sure mine does. In fact the engine runs a little cooler when the acnd is on,


R U talking side cooling or rear cooling here?? My 425 ISL side cooling fan works strictly by engine coolant temperature
makes no difference whether AC is on or off

imgoin4it
Explorer
Explorer
Not sure but I think the fan runs all the time when the acnd is on. Pretty sure mine does. In fact the engine runs a little cooler when the acnd is on,
Howard,Connie,& Bella,
One spoiled schnauzer
2007 Newmar KSDP
4dr Jeep Wrangler