How to Program a 1998 Sierra Keyless Entry
- 1). Locate the data port underneath your driver's side dashboard, on the right hand side of the dashboard.
- 2). Connect your set of jumper wires to the fourth and eighth terminal on the data port. If not numbered, these ports are the fourth and eighth from the left, on the top side of the port.
- 3). Wait for the vehicle to respond by clicking the locks and grab your keyless remote.
- 4). Press and hold both the Unlock and Lock buttons on your remote for around 15 seconds, until the locks cycle again. This will indicate that the remote is programmed.
- 5). Repeat step four with any additional remotes. Program the extra remotes within one minute of the last one, for each one. Remove the key from the ignition once you are finished.
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