My car’s electrical system has started behaving oddly. Last Sunday, it started up fine in the morning (going to church…) but after the service was over the car was completely and utterly dead. Got it jumped and it started up fine, but I noticed that when I hit the brakes the radio would cut out for a second. After arriving home, the car was still completely dead. And last night when driving home from work I turned on the high beams and the car immediately died - no lights, no dash warning lights, nothing.
I have recently used the car to jump start my farm tractor. In hindsight, this probably wasn’t the brightest idea.
I’m thinking I destroyed the alternator, but I want to get a double check before I shell out for a new one.
How old is the battery? If the battery is worn out the alternator won’t charge it.
I suggest having the battery and the charging system tested. Many parts stores will do the testing free.
Battery is the first suspect. Why are you worried about the tractor jump? If it was a 12V system and you hooked up the cables properly, no harm should have occurred.
I have no idea how old the battery is. I bought the car used about six months ago, and have not replaced the battery. It appears to be in decent shape from a cursory inspection - the terminals are clean, the battery is not leaking fluid or anything - but I have not checked the water level or specific gravity of the cells.
I was worried about the tractor jump because although the tractor has a “standard” 12v system, the big diesel engine takes a lot of current to start. I’ve heard that overloading an alternator in this way can harm it.
When someone sells a car they usually don’t put in a new battery, unless the old one is actually failing. As others mention, the battery is the first suspect, then the charging system.
The battery label should give a date on it somewhere. And 12V is 12V, the tractor’s high-capacity charging system shouldn’t have hurt your car.