How do you clean dirty battery terminals?

car battery

If you find that your car isn't starting well, or that your battery isn't holding a charge, it might not be a bad battery or charging system. Before jumping to any conclusions, take a look at your battery terminals. Do they look dirty, or covered in a white powdery substance? That could be the culprit right there. Corrosion can inhibit the connection between your battery cables and your terminals, reducing the performance of both your charging system and your battery.

Fortunately, cleaning dirty battery terminals is an easy maintenance procedure that costs nothing, whereas a new battery can get expensive. If you follow our steps on how to clean your battery terminals and find that you're still having trouble keeping your battery charged, then you should probably have your charging system professionally diagnosed.

Book your Service Appointment at Mississauga Kia or contact our service department.

What You Will Need
You can purchase a battery terminal cleaner from your local auto parts store, but a regular old toothbrush will work just fine. You'll also need a container of baking soda, mixed with water until it becomes a paste. This will work to neutralize the acidic corrosion on the battery terminals.

Step 1) Remove the old cables from the battery terminals.
Loosen the nuts on the ends of the cable clamps and remove the clamps. Always remove the cable from the negative (-), the black terminal first, and then remove the cable from the positive (+), red terminal. When replacing the cables, reverse the procedure (positive first, then negative).

Step 2) Examine the cables for damage or corrosion.
If the cables look excessively worn, corroded, or damaged, then they will need to be replaced. Dirty battery terminals aren't a problem, but if there is extensive damage you should replace the cables and clamps to avoid future problems. Check the battery case and terminals for damage as well. If the terminals are damaged as well, then you will need to replace the battery as well.

Step 3) Pour some of the baking soda mixtures directly onto the posts.
The mixture should foam up as the acid gets neutralized. Dip a toothbrush in the mix and use it to scrub the terminal posts and cable clamps as well. If the toothbrush isn't getting the job done, you can use a battery terminal brush, which will have stiffer bristles.

Step 4) Dry off the terminals with a disposable, lint-free cloth.

Step 5) Smear grease or petroleum jelly (Vaseline, for instance) on the posts to slow down the formation of corrosive deposits.

Step 6) Replace the clamps (positive cable first), and tighten the nut with a wrench.