A plug-in battery charger failed. You may inspect it. It got hot and smoked, and I suppose was a fire hazard. The problem has not been confirmed nor inspected. There were no symptoms of the problem before the failure. - - - - I used the automotive charger to charge a battery after a light had been on overnight, discharging the battery. I removed the battery from the vehicle because the terminals might have been corroded. When I first put the charger on the battery it indicated full and did not start to recharge it, so I used jumper cables to charge the discharged battery from a good battery in my car and left the charger at 10 amps on the good battery at the same time so that battery would not become discharged. I left it to sit, figuring it would take several hours at that setting, and after about 5 minutes I saw smoke. Both 12v wires were hot and insulation burned or melted off. There is damage to the car where the wires rested on the painted plastic bumper and a plastic bit near the battery, and of course the charger is useless. I wrote to the manufacturer on March 28 to make them aware, and ask how to avoid it in the future, and ask if it can be repaired. I have not heard back. - - - - The user manual for this product is at http://manuals.harborfreight.com/manuals/60000-60999/60653.pdf The current year model of this product is at https://www.harborfreight.com/10250a-12v-manual-charger-with-engine-start-60581.html - - - - The charger is sold by Harbor Freight Tools under