Are you having trouble with your 1999 GMC Sierra key fob? Perhaps it’s stopped working, or you’ve purchased a new remote and need to get it programmed to your vehicle. Luckily, programming a key fob for your 1999 GMC Sierra is a straightforward process you can do yourself at home. This guide will provide you with clear, easy-to-follow instructions for both New Body Style and Classic Body Style 1999 GMC Sierra models, ensuring you can regain keyless entry to your truck quickly and efficiently.
Programming a 1999 GMC Sierra Key Fob for New Body Style
If your 1999 GMC Sierra is the New Body Style, follow these steps to program your key fob:
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Ensure All Doors Are Closed: Begin by making sure all doors of your GMC Sierra are completely closed. This is crucial for the programming sequence to initiate correctly.
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Insert Key into Ignition: Place your ignition key into the ignition cylinder of your Sierra.
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Hold the UNLOCK Button: Locate the power UNLOCK button on the driver’s side door panel. Press and hold this button down. Keep holding it until step 9 instructs you to release it.
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Rapid Ignition Sequence (Steps 5-8): Perform the following steps in quick succession:
5. Turn Ignition to ON: Turn the ignition key to the “ON” position. This is the position just before you would start the engine, where the dashboard lights illuminate.
6. Turn Ignition to OFF: Turn the ignition key back to the “OFF” position.
7. Turn Ignition to ON (Again): Turn the ignition key to the “ON” position once more.
8. Turn Ignition to OFF (Again): Turn the ignition key back to the “OFF” position for the final time in this sequence. -
Release the UNLOCK Button: Release the power UNLOCK button you have been holding on the door panel.
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Observe Door Locks: At this point, your GMC Sierra should automatically cycle the door locks, locking and then unlocking. This indicates that the vehicle has successfully entered key fob programming mode. If the locks do not cycle, you will need to remove the key, open the driver’s door, and repeat the entire procedure from step 1.
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Program the First Key Fob: Take the key fob you wish to program. Press and hold both the LOCK and UNLOCK buttons on the remote simultaneously. Continue holding both buttons until the doors lock and unlock again. This might take up to 30 seconds. This step programs the first remote to your vehicle.
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Program Additional Key Fobs (Optional): If you have additional key fobs to program, including existing remotes, repeat step 10 immediately for each additional remote. It’s important to program all remotes you intend to use in one programming session.
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Exit Programming Mode: Turn the ignition key to the “ON” position once again. This action will exit the key fob programming mode.
Your 1999 GMC Sierra New Body Style key fob programming should now be complete. Test each programmed remote to ensure they are working correctly with your vehicle’s lock and unlock functions.
Programming a 1999 GMC Sierra Key Fob for Classic Body Style
For the Classic Body Style of the 1999 GMC Sierra, the programming procedure is different and involves using the Data Link Port (DLP). Here’s how to program your key fob for a Classic Body Style 1999 GMC Sierra:
- Locate the Data Link Port (DLP): The Data Link Port, also known as the OBDII port, is located under the dashboard on the driver’s side of your GMC Sierra.
Alt text: 1999 GMC Sierra Classic Body Style Data Link Port (OBDII) location diagram, showing pin layout and highlighting pins 8 and 4 for key fob programming.
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Prepare Jumper Wire and Connect Pins 8 and 4: Carefully inspect the Data Link Port to ensure that metal contact pins are present in terminals 8 and 4. Using a suitable jumper wire, connect terminal 8 to terminal 4. Maintain this connection throughout the entire programming procedure. It is crucial to correctly identify terminals 8 and 4. The port is typically wider on the top row to help with orientation. Upon connecting the jumper wire, the vehicle should respond by automatically locking and unlocking the doors. This confirms that your Sierra has entered the key fob programming mode for the Classic Body Style.
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Program the First Key Fob: Take the first key fob you want to program. Press and hold both the LOCK and UNLOCK buttons on the remote at the same time. Keep holding them for approximately 15 seconds. After about 15 seconds, the vehicle will signal successful programming by locking and unlocking the doors once more. Release the buttons on the transmitter after you observe the door locks cycle.
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Program Additional Key Fobs (Optional): If you have more key fobs to program, repeat the previous step (step 3) for each additional remote within one minute of programming the previous fob.
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Remove Jumper Wire: Once you have finished programming all of your key fobs, remove the jumper wire from the OBDII port, disconnecting terminals 8 and 4.
The key fob programming for your 1999 GMC Sierra Classic Body Style is now complete. Test each key fob to verify proper operation.
If you encounter any difficulties programming your 1999 GMC Sierra key fob, or if you prefer professional assistance, you can search for local key fob programming services in your area. Simply enter your city or zip code in an online search engine to find a qualified technician near you.
