2008 Chevrolet Impala, Ignition Switch Will Not Turn Off

This 2008 Chevrolet Impala came in with the complaint that the ignition switch would not turn all the way off. This resulted in not being able to remove the key (never try to force a key out) and several lights staying on and running the battery down. Testing starts with checking the RAP fuse. It is the red horizontal fuse in the picture below. Just above the two silver circuit breakers. It was okay and had power present.

The next step is to actually turn the key off so that the battery will not go dead. I used a small screwdriver and removed the rubber plug just below the ignition lock assembly.

With the rubber plug out of the way I could see the white solenoid to the right side of the opening. Using the same small screwdriver I lifted the manual button up on the bottom of the ignition lock solenoid assembly. It only takes a few ounces of pressure to lift the plunger button to the unlocked position so that the ignition can be turned off.

I also removed the cover so that you can better see just what I am trying to accomplish. Sometimes there is a hole in the bottom cover that you can work through if you know where everything is. Also on some models there is a small panel that can be removed from the underside of the steering column cover to easily access the push button on the solenoid.

My finger pushing in on the manual button. While I was there I confirmed that there was no power present on the purple/white wire.

Time to pull the center console to do some testing there. I opened the rear storage compartment door and removed the felt liner to expose the mounting screws.

I used my 1/4″ impact driver to remove the four 7 mm headed screws.

Actually I fully loosened them and left them in place.

I then lifted the simulated wood trim from a round the shifter area. It lifts straight up and then has to be pulled towards the rear of the car for the front edge to clear the storage compartment at the front of the center console assembly.

There are two more screws that have to be removed. One on either side of the shifter. You may have noticed that I am wearing blue nitrile gloves. I am not wearing them to protect the car. I am wearing them to protect my hands from the stickiness and filth in this car. Note the pile of trash in the upper right corner of the picture below.

Next the wiring connector for the power outlets needs to be released. Push in the thumb latch and pull straight up.  Now I had to pull the shifter down into the D1 position and lift the center console from the car.

I disconnected the wiring harness connector at the right side of the shifter assembly and this is what I found. The purple/white wire was broken right where it goes into the terminal.

I released the blue locking bar as shown in the picture below.

Inserted a piece of spring wire and wiggled it around to release the locking tab.

I made up a new wire and terminal. Then spliced it into the original wire and secured it into the harness connector. By the way for testing purposes, the yellow wire is power in from the fuse that was shown earlier.

The power signal goes out on the purple/white wire to the solenoid in the steering column. The black wire at the solenoid has a constant ground on it.

In the pictures below I am showing the relation of the two harnesses as it applies to a TSB #08-07-30-007B: EI08045. The picture below shows the incorrect routing of the shifter wiring harness.

The next picture shows the correct routing of the shifter harness. Make sure that it does not go under the rear wire loop.

Of course I reconnected the harness to the shifter assembly and tested the operation of the locking solenoid. It back working as it should.

The EPL or Electronic Park Lock system is designed to prevent the ignition from being turned off when the transmission is in any position other than Park and the vehicle may still be moving.  If the ignition switch were to be switched fully off when the vehicle was in motion the steering wheel would lock and the driver would not be able to control the vehicle. So as much of a pain in the rear end, this system can be at times, it is really a good thing that it is there.