My '01 Blazer would not start, only had a clicking noise. The eye was still bright green on the battery and the radio, power windows, etc. all worked fine. The truck would not accept a jump, still nothing. I was stuck on the road and had to be towed.
The dealer said he found the tailgate ajar, which drained the battery, and he installed a new battery. Tested the electrical system, said all was fine.
1) The vehicle had been sitting for about 3-4 days. The temperature had dropped to the 30's this week. When I went to start it the previous night, it hesitated but turned over and started. I drove in for about 30 min to make sure the battery was charging. I went out the next morning to start it asd I got the clicking noise, with no start but apparent power to interior devices. I hadn't opened the tailgate for at least a week. Is it possible that it was ajar all week and took that long to actually drain the battery?2) Doesn't this vehicle have some sort of "reserve power" or something similar, meaning if an interior light is left on or a door is ajar, that it smartly cuts off the supply of power to that area in order to make sure it maintains enough juice to start?
The battery was the OEM, about 36 months old. I'm surprised that I never had a problem with it and all of the sudden it wouldn't even accept a jump or charge. Also, I'm surprised that the tailgate being ajar would take almost a week for it to drain the battery, even having used the vehicle during that time.