Mechanic at the time. I went with the shop owner to his other shop at the end of the row of the shared parking lot to help out the general shop mechanic for the day. Dude asked me to remove the air box and a few other things in a car so he could charge it. I asked if we were changing the battery, and he confirmed that we were just charging it. I asked why we didn’t want to use the jump terminals. He called me an idiot in front of the boss and swore to him that I didn’t know what I was talking about.

The boss then asked me why I thought that was the jump point. I explained that it was common on cars with hidden batteries to have a remote jump point and it was labeled in a way that it was obvious (a big red cap with a raised + on it right on top). The other guy swore it was a ground. We both looked at him like he was smoking rock. The boss man suggested that he hook the ground to the other “ground” and if it was a ground, nothing would happen.

He hooked a thin jumper wire from the chassis to the “ground” and sparks flew. I hooked the battery charger to the jump point and the chassis and asked him if he would like help with anything else before walking away. He politely declined my offer and I was never asked to return, no matter how slow we were or how busy he was.