Diff lock light - 97

The diff lock light isn't coming on on my 97. Differential is engaging/disengaging and the dash bulb is good. The dash light does not cycle on during startup like the other bulbs, should it?

Any advice on where to start?

There's a sensor on top of the tcase. Check to see if it's hooked up.

That sensor/switch is adjustable- ie you screw it in until the switch closes when you have difflock engaged. Its a cheapo plunger switch like the brake light switch and prone to failure. To test the switch, screw it out of the tcase and push the plunger in, you should have a closed circuit.

Seems familiar....


You can also test the circuit by simply grounding the main wire to make sure the light is actually working when it should. I just got mine working a half hour ago.

Make sure it is actually locked by rolling the truck back or forward about 10 feet. This seems to be what I was having trouble with. I was just rocking it, thinking that the handle was seating correctly, but I forgot that the LT230 sometimes needs a bit of a length of runway to actually engage! Once it is engaged, then tighten the (tested and working) switch down till the light comes on. Then it should go off when the lever is put back to unlocked position ...if you roll the truck again.

Is there a 'how-to' out there for accessing the switch on a 97? Is it accessed from above or below?

From above. Pull the floor pan off the passenger side. You may also need to pull the center cover. It could also be possible to get at it from the opening under the center console. It is on the top of the right hand side of the LT230, tucked between the transfer case and the transmission. Reachable, but annoying.

Make sure you turn the top nut just a bit, then turn the bottom lock-nut till it is just loose. The whole thing will come out from that point by turning just the top nut.

Clean it with some brake parts cleaner, then test it by grounding one side, while keeping the wire to the dash light plugged into the other side. Push the button on the bottom to see the light come on.

The light started working after a bit more usage. I'll be sure to engage/disengage it regularly in attempt to keep the switch from sticking.