3/7
Check the Battery Inspection Window
If you have a no-maintenance battery, check to see if you there’s a green dot in the sight glass/charge indicator. Green means the car battery is good. If it’s dark, it needs recharging. If it’s yellow or has no color at all (inspect carefully and use a flashlight), replace the battery.
4/7
Check the Condition and Charge of the Battery
If you have a deep cell battery, test the electrolyte in each cell. Squeeze the ball on the hydrometer and draw the solution into the tester. Carefully hold the tester level and write down the reading. Squirt the solution back into the same cell.
The testers are calibrated assuming a battery is at 80 degrees. Add .04 to each reading for every 10 degrees above 80 and subtract .04 for every 10 degrees below. If you get a cell reading that differs from the others by .05 or more, replace the battery. A fully charged battery should have a reading of 1.265 or higher.
If all the readings show fair or low (1.200 is low) but are consistent, charge the battery.
5/7
Check the Battery Tray
Start by taking off your battery hold-down clamp. Disconnect the car battery, starting with the negative cable, then the positive. Use the handle or tie a heavy-duty strap to the ears on the side of the battery and gently lift it out. Be careful; battery acid is dangerous. Don’t drop it.
Once the battery is out, clean the battery tray it sits on and replace it if it’s badly corroded. Batteries are heavy and need solid support. Remember to always wear eye protection and gloves when working on batteries, and never smoke around them!
