Ok, its been a while ... recently I was reminded by my wife that the liftglass open feature is still broken on the Jeep so I decided it was time to fix it and get it over with. From my last post I mentioned that the problem was with the microswitch that is mounted on the Liftgate handle. This microswitch enables/disables the liftglass pushbutton depending on whether the liftgate handle was unlocked/locked. I verified that it was the problen by tempoarily bypassing the microswitch with a piece of wire and the liftglass would pop when you pushed the liftglass button. I removed the microswitchand started looking for a replacement. Here is a picture of the microswitch from the liftgate handle, I have removed the small metal bracket that was riveted to the switch (top of photo):
closeup of microswitch, notice the name "Cherry" on the housing, thats short for Cherry Semiconductors which is a big switch and electronics manufacturer for automobiles.
Now, I could have left this bypassed however that would mean the liftglass could still be opened with the car locked ... not a good idea. I also did not have very good luck finding the microswitch that I needed online, the only part number I found was stamped on the bracket (56007267) which did not show as available on any OEM chrysler parts database. The reason most likely is that the Liftgate handle assembly is the Lowest Replaceable Part in which this microswitch is part of. A new OEM liftgate handle runs about $90.00, a little steep for replacing just the microswitch. "Epay" was no better as everyone on there was selling just the lifgate handles with no switch. A junkyard might have the microswitch but again I would have to buy the whole liftgate handle assembly and there is no guarentee that the switch would be in any better shape.
Sooo ... as a engineer I decided to take the microswitch apart and see what failed on it. I started by drilling out the two holes marked in blue on both sides of the switch as well as cut along the yellow marked seam with a utility knife. This allows the black housing to be seperated from the yellow plastic base.
I slid out the yellow plastic piece from the black switch housing and this is what I found:
Behold another microswitch!!
At this point I'm thinking of those little russian dolls where one splits in half and another pops out and so on ... would I find another switch if I split this on in half?
Well the good news at this point is there are some part numbers printed on this switch, which is also made by Cherry Semicondutors and it is still manufactured. The Cherry part number is E62-00A and available at digikey for $4.59. I order the microswitch and a few days later I had it!
Now we need to remove the old switch from the yellow plastic, best way to do this is use a utility knife and a hammer to cut along the edge using the hammer to tap on the knife and seperate the pieces. I actually cut all the way through and broke off the old tabs. Heres a picture of the old switch seperated, I also drilled out the old tabs and leftover wire bits from the yellow plastic:
Make sure you make the holes in the yellow plastic big enough so that you can slide it over the wires and the switch tabs.
Next you will need to remove the "NO" tab from the new switch, this is the one in the middle, just clip it off.
At this point I suggest test fitting the switch to make sure the tabs fit in the holes. You want to make sure the sides are flush with each other so that the outer plastic switch will fit properly. When you have a good fit thread the two wires though the yellow plastic base and solder them to the switch.
Make sure you don't leave too big of a solder glob as this may cause issues when fitting it into the plastic piece. Press the switch into the plastic piece and it should look like this:
I put a light coat of epoxy on the seam between the switch and plastic. Make sure to wipe off any extra so that it would interfere with the outer switch plastic. After that drys if everything was lined up properly you should be able to slide the outer switch housing over the entire piece. Make sure the outer switch contact is lined up with the inner switch contact.
Now epoxy this housing the same way as the previous step and allow it to dry. And voila! you have a new microswitch. Now I'm at this point, I still need to reattach the mounting bracket. This piece was riveted before but I'm probably going to use a small machine thread screw with a bolt and lock washer. Then I will try it out on the Jeep and post the results, once it stops raining. I know this is a long post but I hope this helps anyone else whos in the same situation.