4wheel drive won't engage.

You should note a change in pressure when you engage 4wheel drive on the vacuum lines to the solenoids under the hood there should be two you see (lil rectangular looking guys). These solenoids change your vacuum from 2wd to 4wd its a free easy fix the dealer won't tell you about; just switch these vacuum lines around you 4wheel drive light will still come on and 4 wheel drive will be off when the light is off (saves you $5-600 on a new solenoid). If it still doesn't work it could be you do not have power to the solenoid I'd check that next. If it still doesn't work its probably that you have a torn diaphram. Which means you have to pull the front pig cover off change out the vacuum pod.

I have 09 Toyota 4runner fwd not engage the light blink