You should be able to see on a scan tool if the coolant sensor is off or not, so you aren't randomly replacing parts.
No codes shown when mine died.
Does anyone know if our trucks will start if the ECM water temp sensor is disconnected?
It doesn't have to show a code. If the coolant temp reads 0 degrees on 30 degree day with the truck running for a couple minutes, you will know that something is wrong.
I know the ecm has a coolant temp correction table that affects spark timing, think there also is limitations built in around -35 to -45 degrees celcius, so if the sensor is disconnectet and it reads it as -40degrees celcius and there are +40 outside its not gonna run good (only if its a NTC if postive then the other way around). I know some ecm's has override functions to combats scenarios like this, but dont have access to enough information about our ecm, maybe some of the true code59 gurus can tell us.
Hope the answer helped a little atleast
Coolant temp was reading normal at the time(s) I was having the no start problem.