On my '86, 300zx NA, the rocker switch on the console turns on the heated outside mirror (drivers side).
2005 nissan quest replacing rear motor mount
You don't tighten it. It has an idler pulley that keeps the proper tension. If this is an old belt and is loose, then it needs replacing. If you have installed a new belt and it is loose, then either you installed the wrong belt or the idler spring is weak and the idler needs replacing.
how to set timing on 99 nissan quest 3.3
Check the fan belt tension.
replace 1996 nissan 200sx se 1.6 tension pulley
The zd30 has a hydraulic tensioner using an idler pulley to automatically tension the serpentine belt.
Where is the crankshaft sensor located
you don't tighten a serpentine belt the tension is supplied by a tension pulley if belt is loose, it is time to replace belt or tension pully if tension pully needs repplacing belt will be worn anyway
Need to know what size engine you have in order to answer your starter problem. 1993 Nissan pickup with v-6
It could be the alternator or an electrical issue