What's the problem?
Recently the 4x4 indicator light on my Jeep's dash stopped working. At first, I thought my 4x4 was out, but after climbing several hills
at Silver Lake I decided it wasn't. So, that must mean the bulb is burnt out. Right? Well, read on to find out.
Tools Needed
- Philips #2 Screwdriver
- Shorty philips screwdriver
- trim removal stick (this is just a piece of wood or soft plasic)
- Aligator clips and some electrical wire
- 13 mm Socket
- 3/4" Socket
Let's Do It
The first thing to do when fixing any electrical issue is to, of course, unhook the battery. Cars are easy to fix, but electrified people are
a little more difficult.
Once the battery is unplugged the next obvious thing to do is check the fuse box. I looked through the scematics and found that
fuse 10 is what controls the 4x4 light, as well as most of the dash. Immediately I knew I was in for more work because the
rest of my dash lights worked, but I checked anyways.
And of course, the fuse was just fine.
So, that means the 4x4 light must be burnt out. So, without too much thinking I disassembled the dash to get to the gauges so I can check the
bulb. Well, actually, I did do one other test first. I tried the actuator test which is done by holding in the Odometer rest button while turn the
key to the accessory position and then releasing the button. This will cause the gauges to go through a self test.
I performed this test and the 4x4 light didn't turn on. This reaffirmed my belief in the bulb theory. Later, I learned that the
4x4 light is not illuminated during the actuator test. So, this test really doesn't help debug the situation, but it's still good if
you are trying to fix something else - like a emergency brake light or something.
Steps to disassemble the dash to get to the gauges
These steps pretty much follow the factory service manual, but I've added a few pictures for clarification.
If you have a tilt steering wheel raise it.
Remove the head light knob.
This is a little tricky and more difficult if you have large hands. The knob goes into a little box behind the dash. On the
top of this little box there is a button. If you twist your arm and shove it up under the dash and disregard as the blood
drips down your arm from scratching it on various sharp things you'll find that little button. Press the button and gently
pull the knob out. Then, curse like heck and get some bandaids so you don't bleed on anything.
Remove the two philips screws that hold the under dash cover on and then remove the plastic cover.
Behind the plasic cover is an aluminum looking cover that is called the kneeblocker. This is removed by taking out the 4 screws
as shown below. Once the screws have been removed the kneeblocker can be removed.
Now, you'll need to direct your attention to the top of the dash to remove the top panel. Manuals will tell you to use a trim strip,
but I didn't have anything that fancy lying around so I used a piece of wood trim. Take your time here because you don't want to
crack anything. The trick is to raise the edge just enough using the soft wood so you can get your fingers under the plastic and
then gently lift up on the plastic so that the hidden snaps will pop out.
I believe there are five of those hidden snaps across the rear edge (the edge farthest from the windshield).
Back under the dash we need to remove 2 more screws from the lower gauge bezel.
Now, back to the top again so we can remove three more screws that hold the top of the gauge bezel in. This is why we had to
remove the top panel so we could get to these screws. To remove the screws you'll probably need the shorty philips screwdriver.
Finally, remove the gauge bezel.
The gauge cluster can now be taken out after we remove four more screws. The gauge cluster will come out all in one piece with
is pretty cool. It plugs into the dash using two connector modules. It just doesn't get any easier than this.
Once the gauge cluster is out we can examine the bulb. In the picture below I've set the cluster on the front seat.
When you get close you can see the annotations on the various bulbs so it's pretty difficult to make a mistake.
The bulb can be removed by pressing gently in and then turning. The first time I did this I thought I broke the
bulb because it was a little sticky. But, it was just a little hard to twist.
So, after all of this work you'd think that I would find a burnt out bulb and this article would come to an end. Unfortunately, no, the bulb was just fine. In fact, I switched the 4x4 bulb with the stupid shift bulb (who uses that light to shift anyways) and reinserted the gauge cluster back into the dash and checked and it still didn't work. I have no idea if the shift light worked because I was in the garage. So, then I got smart and switched the shift light with the brake light and the brake light still worked. Darn. This obviously is not the problem.
What's a Transfer Case Switch
If you look on the scematic you'll notice a little switch that is called S132 on the diagram. Since there isn't anything else in this process this must be the issue.
Finding the switch
For me, finding the switch was the biggest challenge. I posted for some help on the JeepForum web site
and found a scematic of the transfer case that showed where the switch was located. I've circled the switch in orange below.
Here is what the switch looks like when its in stealth mode.
Notice how it blends in with it's surroundings?
Before doing something else stupid I figured I should test the switch first. This is done by disconnecting the
wiring from the switch and then jumpering a wire between the two wires in the switch. Once this is done, go back and
turn on the key and see if the 4x4 lamp indicator light turns on. I used aligator clips with some wire for my testing.
For me, this worked as shown below.
Now that I knew what the problem was, I went to my local Jeep dealer and they had the part in stock for about $26 dollars.
Replacing the transfer case switch
Unfortunately, replacing the switch was a little difficult as well. I had to remove the transfer case/transmission skid plate
so I could get wrenching leverage on the switch. Once the switch was out, I had to take the rubber grommet from the old switch and
put it on the new one. You can see the black grommet in the picture below.
After this, I reassembled everything and I now have a working 4x4 indicator lamp. Whew! That sure was a lot of work to
fix an idiot light. Kind of gives a new definition for idiot light doesn't it!