Bulldozer electrical failure: after the night shift, the machine cannot start, the starting motor failed to turn.

① Battery fault. The starting motor fails to rotate, which may be a problem of the battery. The measured voltage at the battery end is less than 20V （24V battery）, determine the battery fault, and return to normal after devulcanization charging.

②The line is loose. After using it for a period of time, the fault is still there. After the battery is repaired, return to normal. At this time, the author thought about the battery itself is new, so easy to lose power is less likely, so start the engine, found that the ammeter left and right shaking, detect the generator has no stable voltage output, at this time there are two possibilities: one is the magnetic circuit failure, the second is the generator itself cannot work normally. Check the line and found that several lines were loose, and the generator returned to normal after fastening.

③ The load is too large. After a period of time, the battery lost power, the same fault appeared so many times, the reason of the construction machinery is generally a single line system (negative pole iron), advantages: simple line, easy to repair. The disadvantage is that easy to burn down the electrical equipment.