I used to listen to Pat Goss, and he said that it was a bad idea to use jumper cables with a modern car. He said that voltage spikes could ruin the computer systems. Is this true? He was recommending a device that connected the cigarette-lighter sockets of two cars and slowly charged the dead one. I think there was also a product that had a battery and would just charge one car enough to get it started.
I’ve come to doubt some of the things he says about car maintenance, because to me it seems like he seems to have really expensive cars in mind, where a lot of services and things might be more justifiable. A lot of times he has people on his show to showcase products that seem to be geared more for car enthusiasts or collectors than the average Joe. So, what about this issue? If I have a basic car with an engine computer, but no GPS, BMW I-Drive, or anything else, should I be afraid of jump-starting it?
I’ve jump started many a modern car (with computers but lacking the extra fancy stuff) with no problem. I would not, however, recommend jump starting an old car. I tried to explain to my old BF that his 56 Dodge had a different type of battery and that might be a problem, but he didn’t listen.
I’m not thrilled about Goss’s advice either, at least for the reasons stated. I can’t imagine manufacturers designing computers without surge protectors built in. However, he’s right that the slow way of charging is better: the battery will likely last longer if its charged at a slower rate (Fast charging, voltage surges aside, is murder on batteries). Those lighter chargers are slower than a direct battery connection (they are designed to be rate limited because otherwise the fuses connected to either of the lighters would blow out). However, your best bet if you are stuck at home is to hook up your car to the cheapest, slowest car charger you can buy (try Sears). Hook it up and wait…and wait. Almost dead battery + really cheap charger = hours of waiting. Chargers like this are small, so you can often stash it in the engine compartment with the power cord/outdoor extension cord connection. This way, you can charge the battery even in the rain.
Nothing to be afraid of. People who fret about jump starting cars are nothing more than evil demons who hate the Lord, the church, and college football…at least in my experience…
Maybe not hours. I left my interior light on for 3 days. All that happened when I turned the key was a click from the starter. I hooked up a 1 amp charger, and when I tried 3 hours later, there was no hesitation, the engine wound over as per normal. But I’m talking a 2.4 litre 4 cylinder in a warm climate, YMMV.
Yes. Actually, it’s the computer(s) that can be fried, not the whole electronic control system.
This, however, is not true, so long as they’re used properly. Proper use does not cause voltage spikes of any consequence.
Which is different from using jumper cables how? The voltage is the same either way. The amperage might be greater with cables (if they’re quality cables with thicker wire), but that’s irrelevant.
The point of leaving it on for hours is to fully charge the battery, not charge it enough so it can start with no hesitation. Making sure you fully charge a drained battery increases it’s lifespan.
Fierra’s new car is the most computerized car I’ve ever seen, and even it has instructions under the hood for exactly how to use it for jump-starting (or to be jump-started), so I have to think that the systems are a bit more robust than thought.
Yes I did.
One little tidbit Mr. Gross is over looking is that on many modern cars, the power socket is switched via key power, and uses a relay to activate it. In other words you could hook Hoover dam to the lighter socket with the key off, and no power would get to the battery. :smack:
Furthermore, turning on the key induces about a 15 amp drain on the battery, and those little wires connecting the lighter sockets can pass about 5-7 amps. Let’s see now, Mr. Gross, please solve the following equation 7-15= How many amps flowing which way? :smack: :dubious: :rolleyes:
Anyone see a problem here? Anyone? Bueller?
Seriously, who is this guy? I have never heard of him.
1955 was the last year for the 6-volt positive ground systems from Chrysler; they started putting out 12-volt negative ground systems in 1956. This applied to Plymouth-Dodge-DeSoto-Chrysler cars. Trucks may have been different, but all the printed material I have suggests that they switched to 12-volt negative ground in 1956, along with cars. (I have a 1955 DeSoto that I switched to 12-volt negative ground using some 1956 DeSoto parts.) To the best of my knowledge, they never produced a 12-volt positive ground system.
My 2008 BMW came with a specific access point to the positive terminal and a special ground point for the negative cable, and instructions in the owner’s manual of how to proceed, for both receiving a jump or gving one. I’d say they wouldn’t do that if it wasn’t safe.
I think that this warning was directed against jumping a new car by a tow truck. Many tow trucks used 24v (2 12v Batteries) in order to provide a fast jump. This might have caused problems. In all of my research into electronic parts, I always come across modern car electronics being able to survive an 80v “load dump” surge, so I doubt that a 12v to 12v jump would cause any problems.