In a recent Instructable I discussed problems with the instrument cluster on my 1999 Oldsmobile Alero. In that previous Instructable I had believed my ignition switch tested good and I soldered some metal-on-metal connections to by-pass oxidation that may have added a critical amount of resistance to the circuit. Still, the same difficulties returned a few days later. I read articles like this one to see if my 12 year old car with 110,000 miles could be suffering from an ignition switch in the early stages of failure. I decided I wanted to remove the ignition switch from my car for examination and possible replacement, but do it without removing the dashboard.
The Oldsmobile Alero has some "cousins," like the Chevrolet Malibu. But, the dashboard trim in the Malibu is different from that in the Alero. In the Malibu the bezel around the radio simply pries off, and when it is removed the two bolts that hold the ignition switch in place are fully accessible. The Alero is different, though. The same two bolts are hidden behind the dashboard.
For this Instructable I needed:
A 10mm open end and box end combination wrench that I could sacrifice.
A couple of screwdrivers.
A nut driver with a 7mm wrench socket attached.
A torch for heating and bending the wrench as needed (I used a carbon arc torch on an electric welder.).
A vise (for holding the wrench while heating it for bending).
A hammer for making the bend in the wrench as sharp as possible.
A Dremel tool with a cylindrical grinding bit and a burr bit.
A mechanic's inspection mirror.
Auxiliary lighing (flashlight or a mechanic's trouble light)
A Haynes manual for my car.
A new ignition switch.
Step 1: Ignition Switch Bezel
The ignition switch bezel lifts off when pried around its perimeter with a common screwdriver. I will trim away some of the dashboard behind the ignition switch bezel and use the extra space to access the bolts.
Step 2: Working With a Dremel
Step 3: A Suitable Wrench
Step 4: Fitting the Wrench Onto the Bolt Heads
Before beginning I had some concerns about either of the bolts falling out of its hole when fully loosened and lodging down low behind the dashboard. I considered stuffing some newspaper behind the dashboard under the ignition switch, but that really was not necessary. Although the bolts tipped precariously, they never fully came out of their holes and they stayed in place quite well.
Step 5: Removing the Instrument Cluster
With the instrument cluster removed, you can see the upper portion of the ignition switch from the lower right portion of the instrument cluster opening.
Step 6: Access the Switch
My ignition switch uses an interlock cable to connect the gearshift lever to the ignition switch so the car cannot be started unless the transmission is in Park or in Neutral. The Haynes manual fails to mention that this cannot be separated from the switch until the lock cylinder has been removed. The lock cylinder is removed by inserting the key into the ignition switch and turning it to its Run position. There is also a metal retainer in a rectangle on the side of the ignition switch. Press it inward and the lock cylinder can be pulled from the switch. Also, the Passlock wiring harness (white and yellow wires) cannot be removed until the lock cylinder has been removed.
Step 7: The Switch
See the 2nd photo for a view of the back and underside of the switch. The two wiring harnesses and the interlock cable attach here. Even though I pressed the releases on the wiring harnesses, both were very difficult to remove, especially in the confined space behind the dashboard.
The 3rd photo shows the metal tabs in each of the two harness connectors on the switch. The diagram below is from the Haynes manual. Not all tab positions shown in the manual are filled with a metal tab. The table below tells which sets of tabs should have continuity in the various key positions. In my previous Instructable linked in the Introduction I mentioned a test at the fuse panel by which I decided the ignition switch was good. However, when I tested the switch using this table, some of the tab combinations failed the continuity test. At that moment I decided I would spend the money and buy a new ignition switch.
The auto parts store I use is part of a chain. I was able to go onto their web page and locate the specific ignition switch my car uses and to determine my local store had one in stock. The price was also listed. These things were good to know before I had removed enough things that the car no longer starts.