Then it's the switch, switch the right one to the left and see what happens.

Most-likely when you "wiggle" the bad one it will go on again.

__________________
1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).