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Ignition Switch Replacement
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Some comments are from a TD mail list posting by "Fitch R. Williams"

If you have to replace an ignition switch on one of our trucks, it will help to have a FSM. The steps are:

1.    Disconnect negative battery cable(s)). No sweat, pair of 1/2" open box wrenches, and it is done. I notice that the terminals were almost loose, the lead lugs are pinched tight together, and the things clearly need cleaning. I store that observation away for later action.

2.    If the vehicle has a tilt column, remove tilt lever by turning it counterclockwise. Right! .... Takes stronger fingers than mine, but I notice a square wrench flat ... looks mighty small ... I have some ignition wrenches, remember those from days gone by? If you have a 7/32 ignition wrench it will fit the wrench flat on the tilt lever and the thing will unscrew easily. It is also handy for reinstalling it.

3.    Remove the upper and lower covers from steering column (Fig. 1)   I perform a contortionist bending act (the first of many) that would have qualified me for the circus and observe that the screw I can see is a torx drive screw. I look at it, and notice it is bigger than the one I have in the study for the Compaq computer case screws. I go upstairs and get it and prove my eye is good. No problem, I have a 1/4" drive torx T-20 socket and a screwdriver grip 1/4" driver - I remover the center screw. The others however are buried up inside deep holes that I can not reach with my stubby little socket. I rummage in the tool box and find a screwdriver handle T-20 driver, and joy unbounded - the other two are out.

4.    Remove ignition switch mounting screws (Snap-on Torx bit tool TTRX20B0 or equiv).

This is a problem. They are the tamper proof (yeah, right) torx screws. I determine they are also T-20 size. My neighbor, the one that repairs D8 CATs, etc. said just break off the pin with a punch and then take it out. Well, on a CAT this might work, but this thing is all over plastic and pot metal - one blow and I expect to see the whole apparatus including parts that must be reused in shattered bits on the drivers side floor.
I measure the pin in the middle and determine it is about .059" in diameter. I measure the end of the cheap Harbor Freight torx socket and prove to myself that one could drill a .0625" hole in the middle of it and still have significant metal left - the torque on these screws is like 20 in-lbs so they can't be all that tight. so I mount the socket in the milling machine (yes, I happen to have one in the garage - Tim Allen eat your heart out). I also happen to have a .0625" solid carbide bit on an 1/8" shank, and a 1/8" R8 collet for the mill. So I carefully center the torx socket under the drill and with great care and gentle pressure drill a hole in the end of the hardened socket metal. I remove it from the mill, take it over, slip it on the end of the 1/4" screwdriver handle driver, and try it out. Eureka! It works. ZZZZZZZiiiiiippppppppp and the "tamper-proof" torx screws are all removed. I love it when serendipity triumphs over science.

5.    Gently pull switch away from column. Release two connector locks on the 7-terminal wiring connector. Remove the connector from the ignition switch (Fig 3).   Switch and connectors come apart just fine.

6 and 7 go as written, and I get to use my newly customized torx bit again, feeling very smug.

6.    Release connector lock on the JKey-In-Switch and Halo Light 4-terminal connector.

7.    Remove key cylinder from the ignition switch as follows:

(a)    With the key inserted and the ignition switch in the lock position, proceed as follows: Use a small screwdriver to depress the key cylinder retaining pin flush with the key cylinder.

(b)    Rotate the key clockwise to the OFF position. The key cylinder should now be unseated from the ignition switch assembly.

CAUTION:   Do not remove key cylinder at this time.

(c)    With key cylinder in unseated position (key cylinder bezel about 1/8" above ignition switch halo ring), proceed as follows: Rotate the key counterclockwise to the lock position and remove the key.

(d) Remove key cylinder

I map the old switch, and then transfer the key cylinder to the new switch, and determine the contacts are the same. Then I read through the directions for the new wiring harness and the replacement ignition switch connector.

I start through the steps on the kit instruction sheet and end up with the wiring harness all laid bare and ready for the cutters. I decide to match the wire colors and pre mark them for length before cutting the first one, that way I will be sure to have the harness the same length.

The colors don't match! Two of the wires on the new connector are different colors than the wires in that location on the existing connector. What to do? I hate guessing so I read the rest of the directions.

What I figure out is that I can install the new switch and have a truck running good as new, but not better than new as the kit intends. So I do that and put the new harness on hold until I can confirm that if I just match the two odd wires by connector pin it will be OK.

Truck reassembled and running. New harness still in box in garage.

Since then Dominique (AKA John DiMartino - a former dodge Mechanic) wrote me off the list and told me that the replacement connector is because they frequently melt the connector, switch, and wires into a glob which is why it is included. I can leave my original perfect condition connector installed and then proceed to do the wiring harness overlay.

That will have to wait until next weekend.




Last Update: November 2, 1999