Reverse lights on my 1991 Ford Ranger have stopped working. Any ideas?

[Flutterby]

bulbs
fuses
relay switch

 

[Jason]

I have replaced the bulbs and checked the fuses.

 

[Flutterby]

bulbs
fuses
relay switch

 

[Flutterby]

bulbs
fuses
relay switch

 

[jayt]

reverse light switch on the transmission is prob bad.

 

[jayt]

reverse light switch on the transmission is prob bad.