Funny this topic came up. I just had to jump my bus today. I left my CB on for the past 3 weeks and I guess that did it. I hooked up the jumper cables to my saturn and did the high idle thing. I used a twig from a nearby tree to high idle the car
. After about 15 min the bus fired up. It probably would have started quicker if my jumper cables were not so dirty and corroded.
I am glad this worked because I needed to head to the city to get some lumber. I sure did not want to wait for my charger to get the batteries up.