I took my instrument panel off today and noticed some bulbs were missing. What indicators are these for and what bulbs go into them?

 

If you look in the manual it will have a listing of ALL the bulbs. Here's a page from the manual that illustrates that. You will not have bulbs in places where you have no need (options, cab top, psm, etc). Also, there are missing bulb for locations we don't use here in NA versus RoW.

If you don't have a manual, it would help to tell us what year, model, etc so we can tell you what those locations are.

The two on the left are probably CAB top warning and Rollover Protection and the one on the far left is probably PSM. The one up a little higher on the right is probably a RoW indicator. My guess is you have a coupe without PSM.

 

I have a Cab with PSM and the bulbs are missing. Its a 99 996 and I don't have a manual. I think the one on the top is Fuel cap open light. Should I install bulbs in all these places?

 

If you don't have ready access to an Owners Manual and that page isn't posted soon you might try shining a light through the openings to see what the symbols are which would be illuminated by a bulb. My guess is that there's very little reason to add a bulb to a location the factory didn't as the option is either not installed or the bulb just won't work. The exception to that could be if a prior owner removed a known "non problem" CEL bulb.

 

bingo!