Bad temperature gauge or sensor?

[Meanwhile]

(06-30-2020 )Rawze Wrote:  

(06-28-2020 )Meanwhile Wrote:  I just found this on an ASE Diesel diagnosis page.

High Intake Manifold TemperatureECM will turn the engine cooling fan on at 190 ºF. A 20% power derate begins when the mainfold tem-perature reaches 210 ºF. The derate increases to 40% if the temperature remains high.

I'm gonna go check my Intake sensor and see if it's covered with junk.

I was looking thru a CM2250 file today for someone and thought about this post you made while going thru it.

Here is how this persons CM2250 is set with regard to engine fan use and CAC temps...

* From factory, the engine fan is requested to come on if the CAC estimated inlet temp is above 166+F.

* For trucks equipped with a with variable speed engine fan, 33% fan speed is requested at 166-F, 66% at 184-F, and 100% at 199F.

Cummins programming refers to it as "Charge Temperature".

==================
I am not implying this is your issue, but just thought I would follow up with that assumption/question that you posted earlier.

I'm not exactly sure what shut the fan off, it may still be wrong. The long story to this: One of the guys from our shop helped me put a new evaporator in for the AC and charged the system. While the system was being vacuumed out he hooked up his Insite because the fan issue bothered him. In the parameters section he went to fan switches and one switch was disabled. I was looking over his shoulder and there was glare from the sun on his screen so I couldn't see exactly what he did. He said he set everything back to where it was but, when I looked the other day both switches were enabled. I'd have to back and look to see exactly what switch I disabled but I believe it said AC override. After I disabled it, I monitored sensors to watch the coolant temp to make sure the fan came on and off as it should then made sure it came on with the AC. So far everything seems fine.