2005 Chevrolet Impala Ignition Key Will Not Turn All The Way Off

This is a story of how little things left unattended and decisions made in haste can lead to huge problems. The customer came into the shop keys in hand, complaining that the ignition would not shut all the way off in her 2005 Chevrolet Impala and she needed it looked at. I asked where the car was because I assumed she had left it running and only had the remote and other keys on her key chain. It was cold outside and I had all of the shop doors closed and I don’t feel comfortable leaving a car running completely unattended. She said don’t worry the engine is off and the car is locked up. The only thing was she wanted me to look at it soon because the battery may go dead. This concerned me greatly and I asked how she got the key out if the ignition would not turn off. Oh, we can turn it far enough to turn the engine off and my dad had to work at it but he managed to pull the key out! This is getting worse I thought. Little did I know. She left the keys and the car and after I finished what I was working on I went to move the car inside to check it out. What you can see in the next picture is the ignition switch with no key in it. The switch is most of the way off but not enough for the cluster to power down. What you can’t see is the explosion of trash, dirt and sticky film on everything.

The next nine pictures are of a different Impala that I already had that is why the parts look clean.

The first step was to get to the ignition switch to see what was going on. First the lower steering column cover and metal bracket behind it had to be removed. Most of the screws are 7mm and easy to find. There are however 4, 10mm screws that require an extension to remove them. They hold the inner part of the bracket to the dash.

One of the 10mm bolts is located through the hole to the right of my cordless driver. There is a corresponding hole on the right side of the column and the other two are located deep in the dash and are reached along the lower edge of the bracket.

The next step is to remove the front dash trim panel. There are two screws in the upper edge of the cluster opening, a screw on each end of the dash behind the access covers for the fuse boxes and sometimes there is a screw or two along the lower edge around the steering column.

This one required removing the headlight switch knob and shaft assembly. To remove pull the switch fully on and depress the plastic “button” to the right of where the screwdriver is pointing. Then with the “button” depressed pull the knob and shaft from the switch assembly. I had a little difficulty reinstalling the knob assembly into the switch and this is what I actually took a picture of. The knob would not “catch” the inner workings of the switch so I had to go through the slotted hole and work the inner slide mechanism forward and then position the tip of the screwdriver to hold it in place as I pushed the knob and shaft back into place.

Next the hazard and traction control switches has to be disconnected.

Now I could remove the two 10mm bolts that hold the switch in place.

Then I could push the switch into the dash and then pull it out of the bottom of the dash to remove the wiring and cable.

I then removed the shift interlock cable and checked to see if the switch would now turn all of the way off. Success, but not so fast, now the key will not turn the switch back on and the key has to be on in order to remove the lock cylinder for disassembly. Son of a B!*&%$ this just got bad.

The normal progression of this repair is to disconnect the electrical connections going to the ignition switch. Turn the key on. Release the shifter interlock cable. Remove the lock cylinder by depressing the button.

And remove the security sensor wires. But throw all of that out the window. In order to remove the sensor wiring from the switch the lock cylinder has to be removed first. The switch has to be in the on position to remove the lock cylinder. The key will not turn back on for some reason.

Time to start cutting. I chose to use a cut off wheel type cutter and cut the plastic until I could remove the lock cylinder and of course because I did not want to cut the sensor wires I did this in the car.

After I removed the lock cylinder I removed the sensor wires from the switch.

I then had to cut and split the lock cylinder apart so that I could remove the tumblers and recode the new lock cylinder kit.

To see how to check tumbler codes and assemble new tumbler kit click here.

Now that I had that out of the way just what caused all of this. Can we say filth, rust and a sticky film. I knew the problem had to be in the shifter interlock cable and now we are back to real pictures of this car. Seems like the young lady that drives this car had spilled more than one big gulp down the center console and failed to do much cleaning. No surprise there. Between the stickiness, the dirt that collected on the stickiness and the rust that developed under the stickiness the plastic pawl in the shifter could not move properly and it needs to move in order for the cable to move.

The cover over the shifter is held on by spring clips and it has to be pulled up as an assembly as shown below. You can see the six clips that hold it in place. By the way I had already cleaned the cover before I took the picture below.

You can barley see the white shift pawl on the side of the shifter.

You can clearly see white plastic pawl to the right of the picture. A clean up and some lubricant and this one was fixed.

This is not that uncommon of a problem and most cars are not this filthy. Several other factors can cause the same problem. A damp car will allow rust to form. A dusty car will gum up the lubricant and cause the mechanism to stick. If the key in your car will not turn all of the way off I would suggest lifting the cover shown earlier and spray some good lubricant on the plastic pawl and work it back and forth by hand to free it up and allow the key to turn all of the way off.

Now what happened to this car was a build up of rust and stickiness caused the shifter interlock cable to become stuck. A poor decision to force the key out bent the tumblers in the lock cylinder and only a year or so of failing to clean the vehicle resulted in a 800 dollar repair. Those big gulps and laziness sure got expensive.

By the way as a footnote can you tell that Sparky, HATES STICKY CARS!!!!

9 discussions on “2005 Chevrolet Impala Ignition Key Will Not Turn All The Way Off”

  1. If you drill a hole in the bottom of the lock cylinder going directly to the locking tab that must be pushed in, you can remove the tab without destroying the plastic switch housing on a cylinder that does not turn with the key.

  2. I was reading your post because I was having the same problems. I put the car in neutral while it was off and then put it back in park firmly hoping to knock loose some crud that may b in there. It worked. Now i am about to go home and the shift gear cover off to look @ it. Do u think if I just clean it out it will b ok?

  3. Yes, I did have to replace the black housing that I cut. It is the ignition switch by the way. I had already planned on replacing the switch anyways because of the high failure rate. Keep in mind that the only reason that I cut is was because the lock cylinder was damaged.

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