My nephew’s ‘08 Altima 3.5 SE sedan won’t try to crank. The two issues that come up when I google it are the brake switch and the steering lock controller. The brake lights do turn on when the pedal is pressed so that isn’t it and the steering does lock (when it is off) so I assume that means that isn’t what is keeping it from starting.

It will go to the On setting (it is a push button start) and the dash will light up, but the car won’t try to turn over. All the electronics turn on and the fans will blow air. I did hook up a bluetooth OBDII scanner to it to see if it was throwing any codes, but it said it couldn’t connect to the ECU. So I checked the fuses/ relays. Ignition, steering lock, engine cont, alternator, push button and all checked out.

The fob locks and unlocks the car and I also put it in the little dock thing. My dad put a new battery in the fob and reprogrammed it today. We did unhook the battery for at least 15 minutes and also had it on a charger. We also cleaned the battery terminals to make sure it had a good connection.

We did not put a multimeter on the battery and see what voltage we’d get from it nor did we see if we could find a fuse labelled TiP (this was suggested on the MechanicAdvice IRC) to see if it was blown.

This really has my dad and I scratching our heads. Usually we can figure out this stuff between the two of us.

EDIT: After 2 more days of not finding anything even with all the suggestions here, we finally broke down and took it to the local Nissan dealership. It was the ECU.