Where is the backup light switch on a 2000 Chevy Blazer manual transmission?

There isn't a separate backup light switch on a 2000 Chevy Blazer with a manual transmission. The backup lights are activated by a switch built into the transmission itself. This switch is engaged mechanically when the transmission is shifted into reverse. Therefore, there's no individual switch to locate or replace. If your backup lights aren't working, the problem likely lies within the transmission switch, wiring, or the lights themselves.