Back-up lights

Has anyone had a problem with the back-up lights? Checked fuses and bulbs all OK... truck has a manual trans.....
Is there a switrch on the trans... If so is it easy to get to and ho w difficult is it to repair
Any other Ideas

um, what kind of truck, year, pick up or blazer....etc. Anyways yes there is a switch on standards for reverse lights, probly what it is, or a common wire is broken, check the plug located on the frame on the drivers side near the back of the truck. hope that helped