coolent temp sensor

I was checking ECT sensor and the IAT sensor, on my 2003 4.0 L tj, ( have a problem with it running lean ) , 
Checked when it was cold , unplugged the sensor checked the 5V wire they were good , 
the other wire ( only a 2 wire ) is the signal wire ? backed probed it as it warmed up to check signal didn't get one.
checked the other one and the voltage has dropped to the 2 volt range ? 
checked the wire diagram  ( 8w 30 ) if I read it right one wire was the 5 volt the other was a signal wire .
any help would be great.
 

The 5v wire is the signal wire, the other wire is ground. It is a thermistor.
What codes are you getting?

Have beeen getting PO300, ( random misfires )
checked compression, leak down test, coil pack, plugs, injectors, fuel pressure, all are good.
now checking ECT + IAT sensors, took it into a shop they tried but did'nt find a cure. they said to go to a dealer to see if flashing the PCM will fix it, as it runs to lean.

Misfires will cause it to run lean. The o2s will read the extra oxygen from the unburned fuel. What are your total fuel trims at idle and high RPM? Are your 02s reading accurately?

Thanks. will check on them,

Well still have the problem of running rough.
I finely admitted defeat, Took it to the shop I normally deal with, had it for a few days and figured it was in the pcm ?
His suggestion was to go to a dealer , thinking the pcm will need to be flashed or replaced !!
Found another shop that a friend highly recommended that can flash the pcm, thought I would give them a shot.
They did a diagnostic check on it first to make sure nothing else was wrong.
Here is a link to the diagnostic report,  
app.autoserve1.com/report/JuAWco8v4Kz9jZHEf
The only problem they came up with was the IAC, they replaced it, worked just fine, took it for a test drive , then re scanned it to ensure all was good.
started to act up again. It has been in the shop for a week now, The rough idle will come back for a while then go away ( they say when the rough idle starts the timing changes )
Then it all goes away. ( about every 2 hours )
Got a call from the mechanic , he wants to take it to Chrysler, at their cost, to see if they can get better scan the system.
Anyone got any insight on all this??

Thanks for adding the link to that diagnostic report!

I don't have any great insight into your Jeep idle issue. But, based on the content of that diagnostic report, I'd say you best bet might be to let the shop keep working the problem.

Any shop that owns a Pico, knows how to use Pico 7, annotates screencaps AND provides those screencaps to customers using digital inspection software is a cut above, in my experience. Yeah, the IAC may have been a miss, but I can forgive that one given how intermittent the symptoms are.

Yup, that was my thought.
The intermitten (mis and rough idle) started when they changed the IAC. It went in for the rought idle and as you can see from the report the IAC was the problem found, now it comes and goes.
They are going to Chysler to help sort this out.

Finely got the jeep back on Oct 20/2024.
After all the work and testing they sent it to Chrysler with hopes of getting better in-depth testing. Chrysler came up blank, all systems are working properly. Their best answer is (due to age and milage it may have a carbon build up causing the problem). The shop did a fuel system cleaning, combustion cleaner. We still have the same rough idle and stalls out from time to time but goes away for a few hours then returns.
I’m not sure where to go from here .