2007 GMC Yukon Owner's Manual - Page 138

Retained Accessory Power (RAP) Your vehicle has a Retained Accessory Power (RAP) feature which will allow certain features on your vehicle to continue to work up to 10 minutes after the ignition key is turned to LOCK. The radio, power windows, and if the vehicle has these features, the sunroof and OnStar® System, will work when the ignition key is in RUN or ACCESSORY. Once the key is turned from RUN to LOCK, these features will continue to work for up to 10 minutes or until a door is opened. Starting the Engine Move your shift lever to PARK (P) or NEUTRAL (N). Your engine will not start in any other position - that is a safety feature. To restart when you are already moving, use NEUTRAL (N) only. Notice: Do not try to shift to PARK (P) if your vehicle is moving. If you do, you could damage the transmission. Shift to PARK (P) only when your vehicle is stopped. 1. With your foot off the accelerator pedal, turn the ignition key to START. When the engine starts, let go of the key. The idle speed will go down as your engine gets warm. Your vehicle has a Computer-Controlled Cranking System. This feature assists in starting the engine and protects the electrical system. If the ignition key is turned to the START position, and then released when the engine begins cranking, the engine will continue cranking until the vehicle starts or until it exceeds the maximum cranking time allowed, approximately 15 seconds to prevent cranking motor damage. To prevent gear damage, this system also prevents cranking if the engine is already running. The engine cranking can be stopped by turning the ignition switch to the ACCESSORY or LOCK position. Notice: Cranking the engine for long periods of time, by returning the key to the START position immediately after cranking has ended, can overheat and damage the cranking motor and drain the battery. Waiting about 15 seconds between each try, to allow the cranking motor to cool down, will prevent damage due to overheating. 138