Here's a general overview. Specific steps may vary slightly depending on your exact Silverado model (1500, 2500, etc.) and trim level. Always consult a repair manual specific to your vehicle year and model for the most accurate instructions and diagrams. A Haynes or Chilton manual would be a great investment.
Tools You'll Likely Need:
* Socket set (metric): Various sizes, likely including 7mm, 10mm, 13mm, and possibly others.
* Screwdrivers: Phillips and flathead, various sizes.
* Pliers: Needle-nose and regular.
* Wrench(es): Possibly, depending on specific fasteners.
* Ratchet and extensions: To reach fasteners in tight spaces.
* New ignition switch: Make absolutely sure you get the correct replacement for your specific vehicle. The part number should match your old one.
* Wiring diagram: Crucial for reconnecting wires correctly. Your repair manual should have this.
* Pen and paper: To label wires before disconnecting.
* Test light or multimeter: Helpful for verifying wiring connections.
* Security Torx bits (if applicable): Some models may use security Torx screws on the steering column.
General Steps (This is a simplified overview and may not be entirely accurate for your specific vehicle):
1. Disconnect the battery: This is crucial for safety to prevent electrical shorts. Disconnect the negative (-) terminal first.
2. Remove the steering column shroud: This is usually held in place by screws. You may need to remove other trim pieces to access these screws.
3. Remove the ignition switch: This is often the most difficult part. It typically involves:
* Removing the ignition cylinder: This is often secured by a retaining clip or screws. You'll need to remove the key before doing this.
* Accessing the ignition switch: Once the cylinder is out, the switch itself might be behind a panel or secured with screws.
* Disconnecting the wiring harness: This is where a wiring diagram is absolutely essential. Carefully label each wire *before* disconnecting it to avoid confusion when reinstalling. Take pictures as well.
4. Install the new ignition switch: Connect the wiring harness, ensuring each wire goes to the correct terminal. Refer to your wiring diagram. Double and triple check.
5. Reinstall the ignition cylinder and securing components.
6. Reassemble the steering column shroud and any other removed trim pieces.
7. Reconnect the battery.
8. Test the ignition switch: Turn the key to ensure the ignition, accessories, and starter work correctly.
Important Considerations:
* Anti-theft systems: Some Silverados have anti-theft systems that might be affected by replacing the ignition switch. You might need to reprogram the system after the replacement. This could require a specialized tool or dealer visit.
* Security: Be aware of the possibility of your vehicle being vulnerable during the repair process. Work in a secure environment.
Again, this is a general overview. Refer to a repair manual specific to your 1999 Silverado for detailed instructions and diagrams. If you're not comfortable with this repair, seek professional help. Improper installation could lead to damaged components, vehicle immobilization, and potentially safety hazards.
