How to Troubleshoot Car Battery Posts

The battery in your car is the main component in the starting system. It provides the necessary current to start your engine. But many times we forget to give it adequate attention and fail to maintain the battery posts and cable terminals clean and in good condition. If you have difficulty starting your car engine, corrosion around the posts and cable terminals or a bad connection might be starving the starting motor from the current it needs to do its job.

Instructions

1

Locate the battery. Most of the time you will find it at the front of the engine compartment to the left or right hand side.

2

Thoroughly clean the battery top and sides with a clean rag and leave it free of dirt and moisture. This helps to keep the battery from building up corrosion and makes it easier to inspect the case for possible damage. If necessary, mix 1 tbsp. of baking soda with 8 oz. of water in a small foam cup. Use a small wire brush and the solution to clean the battery case. Use water to rinse off the solution.

3

Inspect the battery posts or side terminals. If you see corrosion (a soft white and light green substance) buildup around the posts and terminals, clean them with the baking soda solution and brush.

4

Detach the battery cables from the battery posts or side terminals starting with the negative terminal. Use a pair of wrenches if the terminals are bolted to the post or attached to a side terminal. Use pliers with spring-type terminals. Be very careful not to damage the posts or side terminals.

5

Clean the battery posts or side terminals and the inside of the terminal clamps using a battery post/cable cleaner brush or an appropriate wire brush. Make sure to clean any trace of corrosion. If necessary, dip the cable clamps in the baking soda solution.

6

Connect the battery cables to the posts or side terminals but do not over tighten the clamp or you may damage the terminal and the post.

7

Check for voltage drop to make sure you have a good connection. Start the engine. With a voltmeter set to milivolts, touch the negative battery post with the meters red lead and the battery cable-just before it reaches the clamp-with the meter's black lead. If the voltmeter reads a voltage greater than 0.1 volt, either the terminal needs more cleaning or there is a connection problem between the clamp and the battery cable. Check the positive post reversing the voltmeter leads connections.