hello i just purchased a 08 yukon xl slt with 107,000 miles 2 weeks ago. today it would not start after i got home. the only guage that reads is volts. every thing works like lights, radio, horn, but will not crank over, the display said service 4x4, park assist off, and all idiot lights are on. i tried remote start but still did not start. i let it sit for 20 min and went out and it started right up and all the service messages were now gone and no idiot lights, im stumped.... any advice would be great thanks everyone.