Here's a general guide; however, consult a repair manual specific to your 1999 Chevy Tahoe for detailed instructions and diagrams that match your vehicle's exact configuration. A Haynes or Chilton manual would be a great investment.
General Steps (Automatic Transmission):
1. Locate the Neutral Safety Switch: This switch is typically found on the top or side of the transmission, near where the shift linkage connects. You might need a flashlight and possibly even have to work your hand in a tight space. The exact location will be shown in your repair manual.
2. Disconnect the Electrical Connectors: There will be at least one, and possibly two, electrical connectors attached to the switch. Carefully disconnect them. It's a good idea to take pictures before disconnecting anything, so you remember how it goes back together.
3. Disconnect the Linkage (if applicable): Some NSS's are connected to the shift linkage. You may need to carefully disconnect this linkage. Again, pictures are your friend here.
4. Remove the Neutral Safety Switch: The switch is usually held in place with bolts or screws. Remove these fasteners. You may need a variety of sockets and extensions to reach it. The switch itself may be stubborn; gently work it free.
5. Install the New Neutral Safety Switch: Carefully install the new switch, ensuring it is properly aligned and seated. Tighten the mounting bolts or screws to the manufacturer's specifications.
6. Reconnect the Linkage (if applicable): If you disconnected the linkage, carefully reconnect it now.
7. Reconnect the Electrical Connectors: Reconnect the electrical connectors. Make sure they are securely fastened.
8. Reconnect the Battery Cable: Reconnect the negative battery cable.
9. Test the Vehicle: Start the vehicle and verify that it starts only in the Park or Neutral positions. Test shifting through all gears. If it doesn't start or shifts erratically, you may have a problem with the installation or a different issue.
Important Considerations:
* Transmission Type: This guide assumes an automatic transmission. Manual transmissions have a different starting system and do not have a neutral safety switch in the same way.
* Repair Manual: This is strongly advised. Pictures and diagrams specific to your vehicle's year, make, and model are invaluable.
* Tools: You'll likely need sockets, wrenches, extensions, and possibly a ratchet.
* Safety: Always disconnect the negative battery cable before starting the repair.
* Professional Help: If you're uncomfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Improper installation can lead to safety hazards.
This is a general guide; always refer to a repair manual for your specific vehicle. Working on your vehicle's electrical system can be dangerous, so proceed with caution and if you're uncertain about any step, seek professional help.
