Questioni have a sonata year 2000. and it wont start my dad pulled on a blue box on the battery terminal after my mom jump started the car it had work until my dad did that. what should i do what could it be? i know about auto stuff.
AnswerThe following presumes that the starter doesn't crank the engine. If your engine cranks but doesn't start, the procedures below don't apply.
There isn't much in this box-- as I recall it's black-- except the main charging system fuse. Even if your battery is discharged, you should be able to jump start the car with a sufficiently charged battery. Of course, if the fuse in the box is blown, your battery won't recharge.
I'd primarily recommend checking the battery cables for good contact with the battery. It's possible one of them is loose or corroded, and moving it around caused a bad contact. If the contact is okay, you might do a voltage drop check of the battery cables. First, check the battery voltage to be sure the battery is reasonably charged. It should be near 12.5 to 12.8V if fully charged. If not fully charged, charge the battery first. To check the voltage drop in the positive cable, make the following tests:
1. Clamp one voltmeter lead at the positive battery terminal and the other at the starter lug. Turn the key to start the engine. The voltmeter reading should be less than 0.5V.
2. Clamp one voltmeter lead to the positive battery terminal and the other to the main positive terminal in the underhood fuse block. Again, the voltmeter reading should be less than 0.5V.
Next, check the voltage drop in the negative cable. Clamp one voltmeter lead to the negative battery terminal and the other to bare metal on the engine or transmission. The voltage should again be less than 0.5V.
