Hey fellas, long time lurker. 1st post. I've got a 2008 maxima cvt 3.5, that I can't get to turn over with the key. Put motor in it about 2 months ago, and I can't get it to turn over with the key to save my life. I believed it to be a pnp switch problem, but testing directly at the trans with pins on connector ,( car disconnected ) tested good.
when I was connected to the car though, and testing at tcm connector, seemed like I was getting a problem showing in pnp switch 3.
I finally gave up and took It to a shop. He's got the Nissan scanner, and he keeps telling me the transmission is reporting it's in drive, although the shifter and all associated stuff shows the correct gear at the correct time.
After beating our heads on the wall for a while, realized the only connection electronically is on the cvt valve body, so I dropped pan and changed that switch as well from another valve body. Anddddd mechanic gave up today, that didn't solve it either. We tried different tcm, he stated that the ground that gets supplied by tcm to ipdm is grounding like it should when it clears the start to go. I'm at a loss here, is there anywhere else that or any way that the trans can report a gear status to the car except through the 4 pnp switches?
Wth am I missing ?

 

You said This car had an engine install In the Post. So I can Only assume that the trans was fine before hand. My suggestion to you is to Check the Very Bottom (BLACK) Ipdm plug, to make sure it is seated correctly. Also make sure that None of the Pins are Bent over In the Connector there. If all checks out. My Next step would be to Run and Overlay for testing from the suspected pnp,circuits back and recheck your values.