4X4 Low won't engage

When I come to a stop, put it in neutral, step on the break and switch it to 4x4 Low it won't engage. My 4x4 High works just fine.

Would anyone have any ideas on what it could be?

Thanks
Jay

Found out that my rear brake lights weren't working so I changed the fuse in doing so I found out that the 4x4 low is on the same circut as the rear brake lights.

Should always check the simplest things first.

where is this fuse

under the hood or in the truck?

maybe its the switch,if you have electric or maybe a stick caught a wire on the transfer case

no i just forgot to put it in neutral

it works and has been working the whole time