This is actually pretty easy and should take about a half hour to 45 minutes to get right. Do this exactly, without adding or omitting any steps. Regardless, you still need to use some common sense. I have no control over your work or the design of your vehicle. This should work for any late 1990's early 2000's GM car or truck save the Olds Alero, Pontiac Grand Am or Chevy Malibu. This is because the switch is in the steering column and not on the dash. Cars or trucks with the rubber panel under the ignition lock are good candidates for this fix.
Again, let me remind you to be careful and never work around the steering column without unhooking the negative cable on the battery and waiting at least ten minutes. You're working around a bomb with a hair trigger called an airbag. Do this at your own risk.
You start your car in the morning and notice that the lights come on the dash, but the starter relay doesn't click and the engine doesn't turn over. As you've done before, you let off on the key and turn it back to start. The action rewards you with a crank and the engine catches; no problem.
Eventually you're going to twist and shout, but to no avail. Usually, this is in a dark alley or rainy parking lot with kids in the car. The best bet, especially if your ride has over 100,000 miles is to replace the ignition switch before it fails completely. The ignition switch and the ignition lock are two different parts. The former is a plastic box with a wire harness that lives under the steering column, while the latter is where you put your key in. This switch wears out over time and usually gives you plenty of notice before it finally quits.
You'll need a new ignition switch. (I got mine at Auto Zone for about $40), a Torx T20 screwdriver (bits won't fit) and a couple of small screwdrivers. A socket set with small metric sockets will also help; make sure one is an 8mm to disconnect the battery with. Do this on the negative cable if possible, but the Rendezvous is such a pain that you might have to disconnect the positive cable. Just wrap some electrical tape where the tool might strike a metal surface unscrewing the cable or just be careful, or you'll end up welding the tool to the car (ouch). Wait about 10 minutes for the backup battery on the airbag to discharge. Have a coke, diet coke or a cup of coffee, etc.
You'll have better luck if you take the knee bolster cover from under the dash before you take the steering column apart. The screws are where this cover meets at a right angle to the hush panel under the dash. Remove those screws (there are three of four of them) and this cover should just pry off or be removed by hand. Don't break off the tabs.
If you have tilt steering (and who doesn't), look above the lever and there should be a panel you'll need to pry out so you can get the lower cover off the steering column. Do that and set the panel aside (it's only about a square inch, don't lose it). There are two screws holding the bottom cover to the top and the column. Use your T20 to take them out and gently remove the cover without breaking the tabs. There are plastic hooks on the cover toward the dash. Don’t break these off or you’ll be replacing the cover.
In any service manual, the rest of the steps are going to be removing the ignition lock, the upper cover, and the anti-theft module (if you have it). I looked at mine and saw the only reason you would need to take all this stuff off is to clear the wires on the anti-theft module. If you're careful and DON'T tug on the wires, but move them aside and you can get the ignition switch out. You will need to unhook the harness from the ignition switch, which is a pain in the rumpus to remove, but be patient. Pull on the harness and not the wires while using a flat head screwdriver to release the harness from the switch. The switch has a wheel at the top with teeth and a notch to line up the keep the lock synchronized with same. The new switch will have the notch at the top where it meets the lock, do not move this. Pry out the switch with the screwdriver and make sure the wheel on the new one is in the same position as the old one. As long as they're in the same position, you're in business. If not, reinstall the old switch and move the key to another position, remove the switch and once the notch is on top on the old one. The notch should be on the top in the lock position, so as long as you have the lock locked, you should be okay. Once you're satisfied with the position, put the new switch in hook in the cover and reinstall the screws (snap that little square back in over the tilt lever), snap and screw the knee bolster back on and hook up the battery. Start the car to check your work and don’t forget to set the clock. Maranatha!