Check the charging system yourself. Use an inexpensive digital voltmeter to measure the battery voltage while the engine is running. It must be between 13.75 and 14.75 volts. If that's what you find, it means it's working sufficiently to do the second half of the test, but that requires a professional load tester. If the voltage is okay, either the battery is defective or there's a drain on it.
Thursday, March 10th, 2016 AT 5:36 PM