The GMC Safari minivan is similar to the Chevrolet Astro Van, as all their parts are interchangeable. The multifunction switch in the steering column is designed to control the turn signals, windshield wipers, cruise control and the dimmer switch. When one of these functions ceases to work, it is imperative that you replace the entire switch. This makes the installation process easier, as the switch is held in place by just two screws.
Remove the steering wheel shroud, using a Phillips-head screwdriver.
Locate the two screws holding in the multiswitch. Take these screws out with the Phillips-head screwdriver. You may have to adjust the tilt on the steering wheel to access the screws.
Pull the switch out slowly by hand. This will expose the wiring harness that is attached to the switch. Separate the wires from the harness by prying the tab up with your fingers and pulling them apart. There will be one large harness and two smaller harnesses to detach.
Separate the switch from the steering console by pulling it out with your hands. Pull slowly to prevent the switch from catching on other components.
Attach the wires to the new switch. The new wires should be spliced to fit your vehicle schematics. Simply push the wires into the appropriate harness. They will click when they are seated correctly.
Position the switch to the steering column. Start the screws to ensure it fits correctly.
Tighten the screws with the screwdriver.
Turn the ignition key in your Safari to the "Run" position, but do not crank the vehicle. Test the switch to ensure the turn signals are working correctly. Test the windshield wipers as well as the dimmer switch.
Tighten the steering shroud back around the steering console, using the screwdriver.
