Shift on the fly 4 wheel drive

Maintenance/Repairs
1

i have a 99 chevy blazer zr2 4 wheel drive,when i try to shift to 4 wheel,sometimes it works fine,other times the 4 wheel indicator light just flashes and it won’t go into 4 wheel. what could be causing this?

2

Have you checked your shift linkage?

3

I assume you have auto hubs…I would check their 2 nd. They may not be engaging.

4

Don’t shift on the fly unless you are going below thirty. Go slower than that.