The old switch is shown here next to the auto parts store replacement switch. Notice the gap in the old switch and how tight the seam is on the new one (left).
After disconnecting the battery, remove the lower dash trim cover. The 1987 uses two T-20 Torx screws, while later years use 8mm bolts.
Pre-airbag models have this plastic trim piece where the steering column and the dash cluster meet. Two Phillips head screws are all that retain it.
Next, move on to the steering column itself. If you have a tilt wheel, remove the "priest collar" by unsnapping it from the steel retainer on the outboard side and slip it off the column.
With the tilt collar out of the way, remove the two or three screws (depending on your car’s year) that hold the two steering column beauty covers to each other. Separate the covers.
The old switch, which had been failing for quite some time, was held together with a couple of tie-wraps. We cut the tie-wraps off in order to disconnect the electrical plug.
The ignition-switch connector has a finger grip at one end to help pull the connector free of the switch. If your switch is as bad as ours was, though, make sure you don’t pull the switch apart.
We can see the ignition switch now, but to actually remove the mounting screws, we have to loosen or remove the gauge cluster housing. We opted to simply remove the three lower retaining screws (one on each side for the plastic housing and one on the right side for the support brace) to gain access.
Carefully lift the housing up and access the retaining screws, which are T-27 tamper proof Torx.
With the two tamper-proof Torx screws removed, the ignition switch can be easily pulled from the steering column. Make sure the key tumbler is in the lock position with the key removed, as this is how the new switch is indexed.
This close-up shot shows the tamperproof feature of the T-27 Torx screw. We found our Torx bit at NAPA under PN 33327. Don’t bother trying to drill out a standard Torx bit or grinding out the little post in the screws. The bit is only around five bucks.
Our old switch easily pulled apart due to a failed crimp in the pot metal base. You can see here with the switch separated that the contacts inside could easily short out or burn if they touched the wrong contacts within the switch.
Install the new ignition switch with the provided new tamper-proof Torx screws. Don’t remove the locking wire until the switch is properly seated against the column.
Once the switch is installed, you can remove the locking wire. This wire prevents the switch from moving before it is installed against the tumbler pin.
Inspect the ignition-switch connector for any signs of heat damage and repair if necessary. Ford has a repair connector and terminal kit for this. Carefully push the connector onto the switch evenly until it locks into place. Test the switch now before installing any trim to make sure everything works and that you don’t have any problems.
Reinstall the three screws that retain the cluster housing to secure it.
Next, reversing the procedure, reinstall the lower dash trim and column trim with their Phillips head screws or Torx screws.
Lastly, reinstall the column covers and tilt wheel trim collar to finish up the installation.
Electrical gremlins can surface in any car. Let's face facts. The more options you have and the more wiring running through your car, the more something is bound to creep up. Vintage Mustangs have about four or five wires coming off the ignition switch in the 1965-1966 years--maybe a few more as the vintage Mustang's power options grew. But none of the early Mustangs had wiring throughout the car as late-model Mustangs do. The ignition switch in your typical 1987-1993 Mustang has no less than 11 contacts, some of them with two wires each.
The design of the 1979-1993 ignition switch is simple. A pot metal section and a plastic or nylon section are held together with a few strategic crimps. Within these two halves is a sliding contact switch that makes contact from one wire to another or even to several wires at once, depending on where the switch is moved. The problem centers on those few crimps that hold the two halves together. With age and cycling of the switch, the crimps can weaken or even break, causing the switch halves to separate. This separation can cause any number of problems, from inoperative air conditioning to a car that won't start at all. Worst case is that the ignition switch can even cause a fire. Some model years were included in an ignition-switch recall from Ford, which concentrated on the fact that the switch terminals were too close together, which is an entirely different, and less common, problem.
The best thing you can do is not delay the repair another day and get that old hazardous switch out of your Mustang--which is exactly what we are going to do today with this 1987 Saleen hatchback.