Fan Clutch - MAP Sensor?

[Oil Stain]

Have 2012 3500 Longhorn about 97,000 miles and deleted.

I'm using an MM3 tuner.

My fan clutch is pretty much matching my rpm's while driving around town.

Fan clutch was replaced about 2 years ago.

My thought process and troubleshooting tell me that the PCM is seeing a high temp somewhere and is commanding more fan speed. Now hold that thought.

In the MM3, I found a PID called "Intercooler outlet temp" The reading I'm getting is around 180-230F degrees.

Upon researching, it seems to be the MAP sensor. I unplug it, and the reading pegs at 392F, and when I reconnect it, it goes back down to 180-230F.

It's cold here today, and before starting the motor with just the key on and sensor removed and still connected, I was reading 151F, and it is 50F outside.

Here is my question: Does this sensor heat up to read air pressure like a MAF sensor?

Or should it read the actual temps going through the intake plenum?

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[Badger2078]

Mot sure but at full temp cruising i85 mine reads~120

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[Oil Stain]

Mot sure but at full temp cruising i85 mine reads~120

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Mine is higher now around 160-180F in 50F outside.

I just installed a new Mopar sensor yesterday which brought the temps down a little. I still don't understand why it reads so high on a cold engine and removed from the intake???

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[AK Bob]

Agree my MM3 is showing that my Intercooler Outlet Temperature starts at around 52*F and reaches 123*F when engine is up to normal operating temperature. Not sure where the MM3 is getting this information from. When I monitor my fan rpm with the MM3 it also tends to follow the engine rpm but does confirm it’s spinning faster at higher coolant temperatures.


2014 RAM 3500 (Aisin) 3.73 4X4 Limited Crew Cab Long Bed DRW. Oil Bypass Filter, Fuel Filtration Kit and 50 Gallon auxiliary fuel tank.

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[Badger2078]

Agree my MM3 is showing that my Intercooler Outlet Temperature starts at around 52*F and reaches 123*F when engine is up to normal operating temperature. Not sure where the MM3 is getting this information from. When I monitor my fan rpm with the MM3 it also tends to follow the engine rpm but does confirm it’s spinning faster at higher coolant temperatures.


2014 RAM 3500 (Aisin) 3.73 4X4 Limited Crew Cab Long Bed DRW. Oil Bypass Filter, Fuel Filtration Kit and 50 Gallon auxiliary fuel tank.

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So next is ro determine if this is simulated data compiled from sensors and predetermined mapping or if there is such a sensor. Sadly it is raining pretty hard here.

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[AK Bob]

So next is ro determine if this is simulated data compiled from sensors and predetermined mapping or if there is such a sensor. Sadly it is raining pretty hard here.

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Correct, I agree.


2014 RAM 3500 (Aisin) 3.73 4X4 Limited Crew Cab Long Bed DRW. Oil Bypass Filter, Fuel Filtration Kit and 50 Gallon auxiliary fuel tank.

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[Oil Stain]

This is the Map sensor located on the side of the intake manifold.

If you unplug it, you should see the "Intercooler outlet temp" if you have the correct PID peg to 392 degrees.

There a few intercoolers temp to read; make sure your PID says IC-OT.

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