FJ62, 1988, Sahara, 4wd Light always on

Hey Guys,

2nd post for me on here, am gradually do up my fj62 and keep finding problems.. 4wd was off when i purchased it, the first time i put it into H4 it would turn off... after driving the car for a whole and putting it in an out of L4 back to H4 for several different terrains when i then went back to H2 to highway use the light went off. It worked properly for about 3 weeks after the first fault. However now it is always on again. I cannot get it off no matter what i do.....

Any ideas?

I have tried reversing, no great distances tho, just 5 meters or so...

any ideas? please help, am i out of 4x4? should i leave my front hubs locked?