Are you looking to program or reprogram your key fob for your 1999 GMC Yukon? Losing a key fob or purchasing a replacement doesn’t mean a trip to the dealership and expensive programming fees. For 1999 GMC Yukon models, programming your key fob can be a straightforward process you can accomplish yourself at home with a simple jumper wire. This guide provides you with easy-to-follow, step-by-step instructions to get your key fob working again quickly.
Step 1: Locate the Data Link Port (OBDII)
The first step is to find the Data Link Port, also known as the OBDII (On-Board Diagnostics II) port, in your 1999 GMC Yukon. This port is essential for initiating the key fob programming sequence. It is located underneath the dashboard on the driver’s side. Take a moment to familiarize yourself with the port layout, noting the configuration of the pins. Specifically, you will need to identify terminals 8 and 4, which are crucial for the next step in the programming process. Remember that the port is designed to be wider on the top row, which can aid in orienting yourself correctly.
Step 2: Prepare to Enter Programming Mode
Before you begin the programming, ensure that terminals 8 and 4 within your GMC Yukon’s OBDII port have the necessary metal contact pins. Once confirmed, you will need to use a jumper wire to connect terminal 8 to terminal 4. This connection is what signals the vehicle to enter the key fob programming mode. Keep the jumper wire connected throughout the entire programming procedure. Upon successfully connecting terminals 8 and 4, your 1999 GMC Yukon will automatically respond by locking and then unlocking its doors. This lock and unlock sequence is your confirmation that the vehicle has successfully entered the programming mode and is ready to synchronize with your key fob.
Step 3: Program the First Key Fob Transmitter
With your vehicle in programming mode, take your first key fob transmitter that you wish to program. Press and simultaneously hold down both the LOCK and UNLOCK buttons on this transmitter. Continue holding both buttons for approximately 15 seconds. After holding for the specified time, the vehicle will once again respond by locking and unlocking its doors. This second lock/unlock cycle indicates that the first key fob has been successfully programmed. Once you see this confirmation, release both the LOCK and UNLOCK buttons on the transmitter.
Step 4: Program Additional Key Fob Transmitters
If you have additional key fobs that you need to program for your 1999 GMC Yukon, you must repeat the previous step within one minute of programming the first key fob. This timeframe is important to maintain the vehicle in programming mode. For each additional key fob, repeat the process: press and hold both LOCK and UNLOCK buttons for 15 seconds until you receive door lock/unlock confirmation from your Yukon. Ensure you complete this step for all desired key fobs within the one-minute window.
Step 5: Exit Programming Mode
After you have successfully programmed all of your 1999 GMC Yukon key fobs, the final step is to exit the programming mode. To do this, simply remove the jumper wire that you connected to terminals 8 and 4 of the OBDII port in Step 2. Once the jumper wire is removed, the programming process is complete. You can now test each of your programmed key fobs to ensure they are working correctly with your 1999 GMC Yukon’s remote locking system.
By following these straightforward steps, you can easily program your 1999 GMC Yukon key fob, saving both time and money. Enjoy the convenience of your keyless entry system once again!
