03 Nissan Maxima SE, my daughter's first car.
 

Hello, I'm dB from Rochester, Washington and I bought this car for my daughter because I wanted her to have a mid sized vehicle that would be safe, efficient, stylish and reliable. So far, the car has met all the criteria and she loves it.
A couple of days ago, we encountered our first issue. The check engine light came on solid and stays on. I connected my scan tool to the ODB2 port and my device did not power up. Grabbed my multimeter and checked for voltage on pin 16 and it was zero with the key off. It has 1.2 Volts with key on engine not running. I then tested all the fuses under hood and under dash and all have continuity and all batt circuits have +12vdc. All ign activated circuits have +12vdc key on. The port pins 4 &5 got good connections to ground. I cannot figure out where I'm loosing power to. I could sure use some advise on how to proceed or some suggesstions? Thanks for your knowledge!
dB

Ugh, quite a few places to check actually. The fact that the car still runs should rule out NATS though.