Hey guys just wanted to ask, my xj threw a p0112 IAT code this morning, tested the harness, ignition on engine off and have no voltage bummer! Is there a common place where the harness breaks/shorts? Haven’t had time to dig into just yet but thought I’d ask! Thanks!

 

I could be wrong but I didnt thing the temp sensor worked on positive voltage. One wire was a ground and the other was the signal which was based off OHMs to ground depending on temp.

 

Every source I can find says it supposed to have 5v with the ignition on, I could be wrong too haha I’ve worked on nissans for 13 years, been driving jeeps for the last 8 but they don’t break as much as nissans so I haven’t schooled my self that much on them haha.

 

And I am from the GM world... I know thats how they do their IAT but it is a Jeep so could be different. And BTW - I have owned 3 different Nissans since 07 (still one currently). I know exactly what you mean about them breaking! Just glad they come with a warranty.

 

Haha they are good cars tho they started to get it together around 07 they just had a bad run in the early 2000s. But found the issue!!! Harness was laying on the back of the fuel rail and rubbed threw and grounded the circuit! Thought it was strange it happened today because I just replace the valve cover gasket and nudged the harness around looks like it been that way for awhile tho.

 

There it is! something bit that! I am used to working on 8 or 8.5 volt +/- modified signal systems on big rigs. Anyone else in this industry? It's great to fire up your laptop or desktop and follow a truck and operating parameters in real time as it is driving down the road by satellite. lol

 

Always wanted to work on big rigs sounds cool!

 

Used to be the big guys won... Not any longer, The little guys can get to places and not require moving as much stuff out of the way to get the job done.

The new computerized rigs are a lot more complicated than the general public thinks. I can reset parameters on a truck computer while it is driving down the road under load by satellite remote. Pretty cool stuff...

 

Man that sounds cool! Gonna watch some videos later of it. I like learning stuff like that.

 

Check it out... It's pretty cool. Back in the day we could give drivers "Penalties and Rewards" by adjusting their computers. Look into this topic at Cummins... lol

And we could do it by remote satellite through their Qualcomm system. We could monitor refrigeration units too... all three temp sensors.

"Hey! I'm calling you because your chute is down".

"How do know?"

"Because I am reading your temps and you are about to lose a half million dollar load of Strawberries, stop and check it!"

"Well I'll be darned..." lol

 

Man that’s nuts haha crazy how far tech has come in the last couple of decades

 

Yes, it's pretty wild... So the driver's next statement is a cover Your butt statement...

"The forklift guy must have knocked it loose"

"No... you should have made sure it was still up before you left that Wrap and Gas facility." "And by the way why is your truck throwing an alternative fuel code at me?"

"I added some tranny fluid in the fuel it's good for it."

"Well don't do that anymore...now the computer wants me to shut you down because of emission controls."

"Oh...that's why I have a check engine light?"

"YES!"

lol

 

Man that’s crazy! You can **** them down from a computer?

 

Yep... We can shut the truck down if needed, like if it was jacked, We can cut or increase torque curve, Reset the governor for max RMP's, Set the idle shut down timer, all kinds of stuff from a remote computer. lol