rear fog light?
 

should i connect it? is it always on? or only at night

Huh?

the rear light under the tail lights

No, I know what that is. I just don't understand what you're asking. The one there now is a dummy. You can either buy the Nissan fog light kit with the new stalks (which are reversed because it's JDM), buy the OEM Nissan light by itself and wire it to brake/license/tailight....or you can go with the Evo-R LED fog light kit. The car is pre-wired and has a harness, but there are several ways to get it to work. I have mine wired to the license plate light, so it's on when I turn the lights on.

JDM Fairlady Z Reverse Fog Light

Nissan JDM Rear Fog Lamp Kit - 2009 370Z :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com

http://www.evo-r.net/product/370Z/LED_Rear/index.html

Do a search. There are several threads on this, including DIY's

Depends on how ya rig it up ...

I have mine wired to the left rear tail light so that it burns as a maker light only ... some wire it to the tag light ... you can wire it for a brake light if ya want as well or to burn as both ... you can wire it to flash as a back up warning ... you can wire a switch to turn it on and off as you like

It all comes down to what you want it to do ... check out the DIY section

Good stuff there :hello:

I used this harness:

Motorsport! Rear Fog Light Harness & Illuminated Switch, 09-12 370Z - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts

and this light:

Motorsport! European Rear Fog Lamp, 09-12 370Z - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts