97 jimmy 4x4 lighting question

I was reading my owners manual the other night and it said about the lights on the electronic shift four wheel drive selector being illuminated to show which gear (4H,4L,2H) you are in. My question is , when you are in 2H,is that push button indicator supposed to lit up? My truck only lights up to show either 4H,or 4L. If it is supposed to light up the 2H,what is the replacement bulb number?,is it even a servicable item?(I would think that it would be a very small bulb)