05 granite e-7 aset iegr 2-3 blink code

[Mudman74]

I have a 05 e-7 iegr engine with a 2-3 blink code. FMI 5. I need some help. I have replaced the IAT sensor. The wiring harness is new about 10 months ago. I followed the diagnostic tree for the code and it went away for a couple of days. Now it intermittently comes back on and goes back off. When the lightning bolt comes on the engine fan stays engaged. The plugs look good at the sensor and the ecm. So do the pins. What am I missing?

[Mack Technician]

Is it the IMT sensor or “IAT” sensor?

If you know your harness from point A to point B is in perfect condition be suspicious of ground contacts, even the grounds supporting the newly installed harness. 

Edited October 25, 2019 by Mack Technician

[Mudman74]

Correct me if I am wrong. Isn't the "imt" sensor is on the cegr engine. Either way aren't they located in the same place on the intake manifold under intake ducting?

[Mack Technician]

Sounds like we’re talking about the same sensor. Would make sense if the fan engages full as a default feature in the engine software. Safeguards to give the charge air column in CMCAC full cooling air flow if EECU manifold temp value signal is lost.