Super Duty 4×4
Knob Light Bulbs
F250 4×4 XLT Sport
after I bought my F250, I noticed that my 4×4 knob did not have any back
lighting. I pulled the switch assembly out of the dash and I found the
bulb in question to indeed be blown. I called Ford and they
told me that this was not a "serviceable" part and that I had to buy
the entire switch assembly ($45 in Dec 2007) to replace it. This encouraged me to
research further and I found out a few things.
First, these type of 1/4
twist bulbs are called "neo-wedge" bulbs and the company that made
these particular bulbs for Ford is "JKL Components Corporation".
The typical neo-wedge replacement bulbs I’ve found have a few problems.
First, they are about 1/2 as tall as the 4×4 bulb is and second, the contacts
are located in the wrong spot. The replacement bulbs have contacts located
in the area shown by the blue arrow in the picture below. The Ford bulbs
have contacts shown in the area by the red arrow. I haven’t confirmed this but these bulbs
might also work for the headlight knob illumination.
I ended up buying quite a few bulbs from
ebay that are *almost* exact replacements. The only problem is the contact
location problem I mentioned above. So, I simply removed the dead bulb
from my original housing, removed a good bulb from one of the new housings,
installed the good bulb into the original housing, soldered the connections, and it works
like a charm.
So, if anyone happens to have this problem and feels
comfortable doing what I did (remove dead bulb/install good bulb) then I can
help. I’m going to try to modify these bulbs so that they are direct plug
in replacements, but I don’t have the time to work on it right now. I will
sell these replacement bulbs for $2/each + shipping.
Below are a few pics with some explanation
4×4 Switch Assembly. I was able to pop
it out without pulling the dash apart.
Note the 1/4 twist bulb location in
Original Bulb. I just removed
the green rubber cap and re-used it on the new bulb
New bulb. Recall that the red
arrow shows original Ford bulb contact locations, blue arrow shows new bulb
Here’s the bottom side of the
original bulb housing, after I installed a new bulb in place of the blown
one. I just bent the bulb wires around so they would touch the contacts,
and soldered them. Then reinstalled it into the 4×4 switch assembly and it