2003 GMC Sierra 1500 Pickup Owner's Manual - Page 431

Notice: Damage to your vehicle may result from electrical shorting if jumper cables are removed incorrectly. To prevent electrical shorting, take care that the cables don't touch each other or any other metal. The repairs wouldn't be covered by your warranty. To disconnect the jumper cables from both vehicles do the following: 1. Disconnect the black negative (-) cable from the vehicle that had the bad battery. 2. Disconnect the black negative (-) cable from the vehicle with the good battery. 3. Disconnect the red positive (+) cable from the vehicle with the good battery. 4. Disconnect the red positive (+) cable from the other vehicle. 5. Return the positive (+) remote terminal cover to its original position. Jumper Cable Removal A. Heavy, Unpainted Metal Engine Part or Remote Negative (-) Terminal B. Good Battery or Remote Positive (+) and Remote Negative (-) Terminals C. Dead Battery or Remote Positive (+) Terminal 5-56