Hi.
If your drivers side works, then you have no problem. You're only supposed to have one, on the drivers side.

Years ago, some european car companies offered one or two lamps -- as I remember back then ('70's and early '80s), Jaguars and other english cars (Land-Rover) were a common example for dual foglights, while continent makes like MB and Alpha Romeo had only one. Later, around mid-'80's, Volvo started offering foglights on their USA-market cars, and they had dual foglights.

But around 1991 or '92, most companies started to only install one foglight, on the drivers side -- Volvo followed suit, and has only had a working foglight on the driver's side since that time, at least in cars for the USA-market.

In many models, Volvo retains the socket for the other side, but just didn't include the electrical conductors in the wiring harness. In my '93 240's, the hole for the socket is present, but the actual socket (with electric tabs) is left out.

Believe that rear fog lights are only supposed to be one. Believe it or not that is the way some of the earlier models are. Folks will think it is the brakes or so I have heard. Strange for sure.

dick