Temp sensor 5v ref is not shared with any other sensor...they are stand alone circuits(IAT and ECT) What does scan data show? NTC's are pretty straight forward. Unplug the sensor...scan data should show -40F, jump the 2 harness pins together...scan data should show 284F. If that's the case....the ECM/wiring is fine...you have a sensor/connection issue. If that doesn't happen start following the 5V ref wire back to the ECM....either it's shorted to ground somewhere or the ECM is questionable.Good luck!
My scan tool shows in "Live Data" that the IAT is at 372 F. with the sensor unplugged. With the a jumper installed at harness plug, I get no change in the temperature reading on the scan tool (372 F)
It is sounding like I have a open wire going back to the PCM?
