Acustar steering column ignition lock service
The Acustar steering column in most 1990 to 1996 Chrysler-built vehicles is easy to identify: the square pushbutton for the hazard flashers is near the middle of the top of the square plastic housing. The ignition lock has a chrome or black receptacle for the ignition key, surrounded by a transparent “halo” ring for lighting. Generally this is a reliable column, reasonably well designed, but there is a relatively weak point; whether by abuse (attempted theft of the car) or by wear, or by simple random luck, the ignition lock can come apart from the switch and spin freely. If you’re lucky, this means you must fiddle with the key receptacle to line it up with the switch before you can insert, operate, or remove the key. If you’re not so lucky, it means you’re either not going anywhere or you’re leaving your keys dangling from the column.
The problem is a small metal pin that protrudes outward from the side of the lock cylinder, anchoring it to the ignition switch. Sometimes the pin simply falls out and gets lost, leaving the lock cylinder free to shift and drift little by little until it pops out. But even if the pin stays put, the part it protrudes outward into is made of plastic. A thief with a slide-hammer will quickly break that plastic in the process of yanking the lock. The repair in both cases is the same, and it’s not difficult, but you will need one special tool: a T-20 tamperproof Torx driver or bit. What makes it “tamperproof” is the hole in the center of the drive star, meant to fit over a matching round nub in the center of the screw head, which prevents use of a Torx T-20 driver. Tamperproof T-20 drivers or bits are easily available at a well-stocked tool, hardware, or auto parts store, defeating any real tamper-proofing, but there we are.
The steering column’s square plastic housing is two pieces: upper and lower. Three screws hold housing halves onto the column; one of them is the first tamperproof T-20 screw you’ll encounter. It’s in the middle of the bottom housing. Unscrew it, then insert a long slim driver into the two tunnels close behind the steering wheel—Philips, regular Torx T-15, or Allen hex depending on when and where your car was built—to remove the other two screws.
Then remove the column tilt lever, if equipped. It simply unscrews—usually by hand, but there are flats on the lever shaft if yours is extra tight and needs persuasion with a wrench or pair of pliers.
Now you can gently but firmly grasp the upper and lower housing halves and pull them apart, exposing the inner works. You’ll see the multifunction switch—turn signal, windshield wiper, headlamp high/low beam, and hazard flasher—on the left. If you need to replace it, now’s a fine time; you’ll need a tamperproof T-20 Torx driver with a slim shaft because clearance to the screw heads is very tight. On the right you’ll see the ignition switch, its light halo, and the ignition lock. That’s where we’re focusing in this article.
The ignition lock is held to the column with tamperproof T-20 Torx screws. When you’re removing or installing screws in the steering column, work deliberately and keep your eyes on what you’re doing. There’s a lot of pot metal involved, and it’s easy to break or cross-thread a screw. That’ll really spoil your day, so pay attention.
Perhaps it’s just a coincidence that you can almost spell “ignition” using letters taken from the word “incognito.” Or perhaps it’s because of this Chrysler ignition lock repair kit, part number K4411 456. It doesn’t appear in any Chrysler parts catalogue, doesn’t come up as a valid part number in a part number search, there’s no useful information to be had by a Google search, and yet…here it is, genuine packaging and all:
I obtained this from a well-stocked local locksmith shop. I’d gone in asking for a price on a new lock cylinder keyed to match my existing car key—who wants to carry around two keys instead of just one?—but when he asked what the trouble was with my lock cylinder and I told him, he put this kit on the counter and said it would effect a good and durable repair for much less money than a new cylinder and a rekey job. Seems this kit came with service replacement lock cylinders for a while, when cars with this column were new enough to be on the high-theft list, and since it wasn’t always needed, a good locksmith shop is likely to have a pile of them.
The repair kit consists of a stamped steel bracket and two special screws. The bracket gets placed on the ignition switch body as shown. See that the ignition lock is fully seated in the ignition switch, then install the short screw from the kit so it will will protrude into the ignition lock cylinder, holding it in place as a functional replacement for the missing pin. You may be tempted to tighten the screw all the way tightly. Don’t; if you do, it’ll bind the ignition lock and prevent it turning easily. Tighten it just snug, then back it off slightly. There’ll be plenty of screw engagement length with the lock cylinder, which won’t go anywhere, and there’ll be no binding.
The other (long) screw from the kit holds the ignition switch to the column. It’s longer than the original screw you removed, to work with the extra thickness created by the metal bracket. These screws that hold the ignition switch and lock assembly to the column must be tightened securely, but be careful not to break them.
While doing this repair, it’s not a bad idea to replace the halo light bulb. Originally this is a tiny incandescent bulb #37 that works fine. Instead, I used a green "LED bulb" that fit directly in the socket. “LED bulbs” are unsafe and illegal to use in any of a car’s exterior lights; the amounts and distributions of light are different enough that exterior lights can’t work effectively or legally when fitted with any kind of LED “bulb.” But there’s no such safety concern with interior illumination. I wanted to see if the ignition halo light delay—a thermal bimetallic unit just like Chrysler has been using since the 1960s—would still work with it, and it does. The halo light is now a brighter, more pleasing color of green.
Assembly is the reverse of disassembly. Enjoy!
Editor’s note: Acustar was Chrysler’s parts subsidiary, split off in 1987.