Here's a general outline of the process. Specific steps may vary depending on the exact trim level and options in your Suburban. Consult a repair manual specific to your year and model for detailed diagrams and instructions. A Haynes or Chilton manual would be helpful.
1. Preparation:
* Disconnect the negative battery terminal: This is crucial to prevent electrical shorts and injury.
* Gather tools: You'll likely need a trim panel removal tool (plastic pry tools are ideal to avoid scratching), various screwdrivers (Phillips and possibly flathead), possibly a socket set, and possibly a wiring harness connector removal tool. Having a flashlight will also be helpful.
* Find the repair manual: This is HIGHLY recommended. It will guide you through the specific steps for your vehicle and show you precisely where components are located.
2. Accessing the Heater Control Panel:
* Remove the trim around the heater control panel: This usually involves carefully prying off the surrounding trim pieces using your trim removal tools. Work slowly and systematically to avoid breakage. The trim pieces are usually held in place by clips.
* Disconnect the heater control panel: Once the trim is removed, you'll likely find screws securing the heater control panel itself. Remove these screws. Then, carefully disconnect any electrical connectors attached to the back of the panel. Take pictures or make notes of how the connectors are attached to avoid confusion during reassembly.
3. Replacing the Heater Fan Switch:
* Locate the fan switch: Once the control panel is removed, you'll be able to locate the heater fan switch itself. It's likely a relatively small component within the larger control unit assembly.
* Disconnect the switch wiring: Carefully disconnect the wiring harness connector(s) from the back of the fan switch. Again, take pictures or make notes.
* Remove the old switch: The switch might be held in place with screws or simply clips. Carefully remove it.
* Install the new switch: Install the new switch, ensuring it's properly seated. Reconnect the wiring harness connector(s).
4. Reassembly:
* Reinstall the heater control panel: Carefully put everything back together in reverse order of disassembly.
* Reconnect the electrical connectors: Make sure everything is securely plugged in.
* Reconnect the battery terminal: Reconnect the negative battery terminal.
* Test the heater fan: Turn on the ignition and test the heater fan at different speeds to ensure the new switch is working correctly.
Important Considerations:
* Dashboard removal: In some cases, you might need to partially or completely remove the dashboard to access the heater control unit. This is a significantly more complex undertaking and requires more specialized tools and knowledge. Again, consult your repair manual.
* Airbag deployment: Be extremely cautious when working near the dashboard and airbag components.
* Electrical safety: Always disconnect the battery terminal before starting any electrical work. Avoid touching exposed wires.
* Parts sourcing: Make sure you purchase the correct replacement heater fan switch for your specific 1999 Chevy Suburban. The part number will be essential. Your local auto parts store can assist with this.
This is a general guide. You should consult a repair manual specific to your 1999 Chevy Suburban for the most accurate and detailed instructions. If you're not comfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improperly performing this repair can lead to further damage to your vehicle's electrical system.
