light on dash
 

I got a little 4x4 light on my dash that goes on win you engage 4x4 and the last couple times the light refuses to light up , any ideas what would cause this

Need more info.

Year and model truck
Knob or lever shift
Does 4wd actually engage or not?
Are you trying to engage 4wd Low without foot on the brake and in neutral?

Its a 2007 F150 crew cab XLT and its a switch on the dash.
4x4 does work win I turn the switch to 4x4 low or high, I can also hear it engage. iv looked at all the wires under the truck and they seem to be in good shape.
No blown fuses that I can find, also win I start the truck it will flash on then back off. and win i turn the switch to engage 4x4 it does not flash for me.

Check the IWE vacuum solenoid under the hood on the passenger side firewall near the battery.

I checked the vacuum to the solenoid , its working good , no moisture or freezing going on, actuators are in gageing ok