I have the error code P0112 on my 05 Caravan which is the "Air intake temperature sensor circuit low input"

For the heck of it, I went out and bought a new temp sensor, but the the code comes right back. I checked for +5vdc at the
connector on terminal #1, but I got 0 vdc. I checked terminal #2 for a continuity to ground and that was good.

Thinking that I have a bad connector, I next stripped back some insulation on the purple lead wire to the connector
to see if I had the 5 volts there, but there was still nothing.

Any ideas where to check next??

That 5v comes from the computer. It probably feeds more than one sensor as well, though it may not. You will have to look at the schematics, see where that 5v is coming from and find the loss. Probably a broken wire.

Probably help if you told us what engine it had.

I'm having trouble finding schematics of the wiring on line. I would like to be able to go to the ECM and check the 5 vdc source there, if possible.

Intake Air Temperature (IAT) Sensor
Intake Air Temperature (IAT) Sensor Wiring
Powertrain Control Module (PCM)

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?

High temp means low resistance....maybe a short to ground in the 5v? Low temp is high resistance.

Strange, I took wire resistance readings to ground at the IAT plug and I got 348K ohms on the #1 terminal and 1 ohm on the #2 terminal.
These reading to me show that the #1 terminal wire is not grounded as it should be and also the #2 terminal wire is grounded as it should be.

Without a diagram I'll assume pin 2 is sensor ground(as it should be) That leaves pin 1 which should show 5v. I'll assume it doesn't....if it did your scan data would show -40F with the IAT disconnected. Chase that wire back to the ECM. A diagram with ECM pinouts will help. Good luck!!