I’m having an issue with my 88 Toyota 4wd with 22re, manual locking hubs and manual transmission. I recently had my locking hubs replaced. When I locked my hubs and tried to engage 4wd my indicator light didn’t come on. I checked the bulb and that was fine. What should I check next? Thanks in advance

 

There is a switch at the passenger side of the transfer case that lights the 4WD light on this vintage truck. All it does is light the 4WD light.

I think on an '88 that it is only a one wire switch, so it must only make a grounding when it is closed. Maybe your switch is disconnected, or its wire is parted somewhere.

The good news is that you should have four wheel drive when the case and hubs are properly selected, whether or not the light lights up.

On other trucks that have ADD (automatic axle disconnect), if the switch doesn't make, there can be no 4WD.

 

Like Millball says^^^
Did it work before locking hub work?
Do other dash indicators work?
Find the FWD indicator switch and do voltage check.