FJ62 - 1988 4WD Light stuck on

Have you tried driving in reverse for a couple of metres ? Running through the gearbox a few times ? Changing from second low to 2nd high at low speed ? etc

Will it be on 4WD? or just 2WD?

my 60 series had it's light stuck on once when i tried to disengage 4wd with the front hubs still locked

i unlocked the hubs and tried again and it worked (i think - nothing has blown up yet)

Hi justin The t/case shifter is vaccum activated.
There are 2 vac hoses into the shift mechanism ,one for in 4wd ,the other for out of 4wd.
If you think its stuck in 4wd the hoses can be swapped,so the button function is reversed,in on is off ,off is on.
Causes for them to malfunction is lack of vaccum caused by leaks.
Trace the 2 hoses back to the solenoids on the firewall on the rh upper side.
If no leaks and the hoses are on correctly follow the vac lines from the solenoid to the inlet manifold.
If all that checks out it may have a leak in the diapragm on the t/case which is easily dismantled and repaired.

To test if its in 4wd ,unlock the fwh and turn the front driveshaft by hand,if it wont turn its in 4wd.

Dont go hitting anything with hammers
You can save a lot of headaches and get a better understanding of how it works with a Gregorys manual for $29.95.

Here is a thread on someone who cant get 4wd,probably the same reason you cant get it out.
forum.ih8mud.com/showthread.php?t=98017

I suppose a solenoid could be dead but I cant remember hearing of one dying.
Its always the other things I mentoned.
You could also check there is power to the solenoid and of course the button has been known to fail as well.

The vaccum is constant while the engine is running and the solenoid switches it from one hose to the other.
At least one side of the vaccumm should work regardless.