Found this the other day .. might help?
If you are installing in a Nissan Versa, or internet rumor has it any Mazda or Nissan, removing the stereo panel will require disconnecting the airbag indicator light, which will not self reset. To avoid paying your dealer around $100 to reset the error (if you do this with a good stopwatch, and it doesn't reset after a few tries, you may have an actual airbag error, so get it serviced) try the following steps. Reportedly worked on a 2003 Mazda Infiniti, a 2007 Nissan Versa, and did work on my 2008 Nissan Versa.
Perform the following steps in order.
1. Turn on ignition without starting and wait 7 secs then turn to acc position and wait 4 secs.
Repeat above step three times without pause inbetween.
2.Turn on ignition without starting and wait 7 secs then turn to acc position and wait 3 secs.
3. Turn on ignition without starting and wait 7 secs then turn to acc position and wait 2 secs.
4. Start car and wait 3 secs then turn off wait 3 secs and start car.
I wish I knew this before installing a radio in an 07 Sentra. If you unplug the indicator light for the passenger airbag, the airbag light on the dash will come on. Really freakin' annoying if you ask me. Luckily, it was under warranty. I didn't have to pay for anything.