Yesterday at work they blocked off the section of the parking lot where I usually park so that they could trim some tree branches. I parked at the end of a column, right by a receiving bay of Building 2, and I reasoned that there wouldn't be a problem because the only thing I was blocking was a tractorless trailer that had been sitting in the bay for MONTHS, if not longer.
Wrong. Not long after I sat down at my desk there comes the announcement over the loudspeakers that a car matching my description and license plate needed to be moved. Swell. So I moved it. And when I got out to the parking lot at the end of the day, I discovered that I had left my lights on and the battery was dead, dead, dead.
It was a below-freezing, foggy day yesterday, ice crystals falling out of the sky like so much confetti, and that's probably why I had turned on my lights to move the car. But of course, there's no announcement over the PA system that someone has left their lights on. Oh no. This is the second time I have left my lights on, but they won't say anything unless I've parked outside the lines.
But I came prepared, you see. I had purchased the Schumacher MityMite Automotive Jump Starter/DC Power Source, model PS-70A. It's a 12V, 70A charger. Car batteries are 12V. The thing was fully charged. I attached the red clamp to the battery's positive terminal and the black clamp to chassis ground.
I turned the key. Nada. Not even a flicker. I left it sitting there for awhile, and still nothing. Lucky for me, someone came out of the building and went to his car, and he had jumper cables. My car started readily on the first try with the live car battery.
So what gives? How come the thing didn't work as advertised? I've seen the portable chargers work before; when I called GEICO road service, the tow truck used one instead of his own truck battery.
I've been all over Al Gore's innertubes, trying to find the answer and leaving disparaging comments whenever feedback is allowed, but I still don't know what went wrong. I am absolutely sure that the cables were connected correctly and that the clamp was contacting the terminal. It's not my first time jumping this car (both as jumper and jumpee), so I have had success in the past.
Pisses me off. These chargers aren't cheap. If I can't jump my car with it, what's it good for?
UPDATE: I asked on
Yahoo Answers, and they said that to jump a dead dead dead battery you need 300-650 amps. These little things work only if you have a weak battery. I'll be returning the item, if I can, in exchange for some jumper cables.
UPDATE II: I tried to return the thing, but I didn't have a receipt (from two months ago), so I got the jumper cables anyway and I've decided to keep it as an emergency supply. It has a cigarette lighter outlet, and I have a DC-to-AC inverter with a conventional plug, so in an emergency, I can use it to power a small radio.