Ok, I know i'm stupid,save it!!! Yesterday, I when to buy an electric arc welder considering it was the best solution to weld something in my engine compartement. I did what they said and finish with a good result, for the welding...However, When i come to start the car, I notice the car is missing a lot of electricity.... As an example, while the radio is playing, if I touch the brake (enought to make the lights go on) my radio will show insufficent power and stop playing... or when I turn on the headlights, my fan will not work anymore.. It looks like there is not enought power from the batt or alternator. So i decide to change the alternator.. but still no improvement... THEN.... I look at the last page of the instruction booklet, and in small letter "Always disconnect the battery before welding"..!!!!!...Does anyone know what I might have damage in my car?? BTW, it's a 1990 JEEP cherokee!!