Last Updated: 30.12.2021

Look under the hood of your modern vehicle and you are going to see all kinds of wires, sensors, and modules, among other things.

This means all these things are electronic and they need a good electrical supply, which starts at the battery. So, you’ve got to have good electrical connections or contacts on the battery. Fouled electrical contacts tend to have higher contact resistance because of arcing caused by carbon buildup and corrosion.

But don’t worry, we’ve got several tips and tricks on how to clean electrical contacts. This guide also provides additional information that will help with the maintenance of your electrical contacts. 

What Are Electrical Contacts?

engine showing battery and electrical wirings

These are the most important elements in any electrical device in your vehicle. Electrical contact features two parts that are made of conductive material that allows electrical current to pass through when the gap between the two parts is opened or closed.

The gap is usually an insulating medium, such as vacuum, air, or any other insulating fluid that is electrically conductive. The contacts materials are normally highly conductive like gold or silver. But some economical electrical contacts are made of cheaper conductive materials.

Electrical contacts are engineered to be normally closed or normally opened. Some contact pads may be crowned while others are not.

Signs That Your Electrical Contacts Need Cleaning

These are the most common signs that will let you know that your electrical contacts need cleaning.

Corrosion

corroded car electrical connector and wirings

Accumulation of grease, dirt, and contaminants in your car’s electrical system can eventually lead to contact failure as well as malfunction.

Electrical contacts usually suffer fretting corrosion. You can consider fretting corrosion to be an increased deterioration or degree that takes place because of repeated oxidation or corrosion of the freshly abraded surfaces. When electrical contacts of your automobile are exposed to vibrations of contraction and expansion, the micro-movements between the contacts generate fretting wear.

Contacts that are made of cheaper materials and then coated with gold or sliver usually suffer the most when the gold or silver plate is worn out.

Electrical Arcing

When two electrical contacts are attached, current will pass through them. But when the contacts are pulled apart an arc is formed as you disconnect the electrical supply.

The formation of the arc is because electricity wants to keep on flowing even after disconnecting the two contacts. The arc ionizes the air that exists between the two electrical contacts. The energy and temperature of the arc can easily damage your electrical contacts. The burning capacity of the electrical arc is usually increased by the amount of current flowing through.

If arcing occurs repetitively, it usually damages the contacts, exposing them to carbon buildup as well as corrosion.

What Is a Contact Cleaner?

This is a relatively new technique for cleaning electrical contacts. With that said, an electrical contact cleaner is a specialized cleaning solution that is made up of a cleaning agent like isopropyl alcohol and compressed air.

It is the perfect choice for getting rid of carbon buildup, corrosion, oils, grease, and foods. It usually does a great job of dislodging foreign elements when cleaning electrical components. 

You can also achieve good cleaning results when cleaning your electric contacts with nail polish remover, white vinegar, or rubbing alcohol. The best contact cleaners on the market normally have a high flash point, which will ensure the contacts remain energized during the cleaning process.

A cleaner with a low flash point could destroy the parts that are being cleaned and even start fires that may cause you injuries.

What to Look for When Selecting a Contact Cleaner

These are the most important things we think you should consider when selecting the ideal contact cleaner for your do-it-yourself (DIY) project.

Flammability

Your safety when using a contact cleaning agent is very important, and that’s why you have to consider the flammability of the cleaner.

You should pay close attention to the flashpoint of the cleaning solution. This refers to the lowest temperature at which an electrical contact cleaner can form an ignitable mixture when exposed to air. 

The ideal flash point should be above 145 degrees Fahrenheit. A cleaner with this specification is considered to be a non-flammable liquid. This is a very important aspect when you want the parts you are cleaning to remain energized.

If you settle for an electrical contact cleaner that has a low flash point, then the liquid can ignite, destroying your components. You could also get injured in the process when the liquid ignites unexpectedly.

Fully Evaporative 

The next important thing to consider is whether the cleaning agent is fully evaporative or a lubricant. Choose a cleaner that is fully evaporative when cleaning electrical contacts.

This will ensure there is no residue left behind that could otherwise cause grime and dirt to collect. Accumulation of dirt and grime can obstruct the flow of electricity when they come between electrical contacts and their contact points. A proper cleaning procedure requires the contacts to be residue-free.

You may not want contact cleaners that contain lubricants because they will leave residue after cleaning, which may affect the performance of the contacts.

Water-Free Formulation

This is an important factor considering that most electrical contacts are made of material that can oxidize and corrode in the presence of moisture. The best cleaning agent should have a water-free formulation.

Toxicity

When selecting a contact cleaner you don’t want a cleaning solution that has hazardous ingredients that could result in it being regulated to the extent you could no longer use it for your DIY contact cleaning project. Preferably, consider a cleaner that doesn’t contain RCRA or SARA listed ingredients.

Precision Contact Cleaners

It is important to choose a contact cleaner that offers precision contact cleaning. Such a cleaning solution will make it easy to clean impossible or difficult to reach places. 

Precision contact cleaners usually come in a trigger spray foam or aerosol design. They emit particles evenly over the surface of contacts and produce very little waste. 

How to Clean Electrical Contacts

What You Will Need

  • Electrical contact Cleaner
  • Contact cleaning tool kit

Step-By-Step Guidelines

Step 1: Do a Visual Check

do a visual check

Start by doing a visual inspection of the contacts to determine if they are burnt, worn, or contaminated by environmental substances. The engine should be off and make sure the power supply to the electrical components and electrical contacts is disconnected. 

Check the surfaces for pitting or other wear that could cause electrical arcing. Then you can begin the cleaning process. 

Step 2: Remove Corrosion and Carbon Buildup

remove corrosion and carbon buildup

Use an appropriate tool to get rid of corrosion before applying the contact cleaner. You can use a tweezer-type tool to get into contacts that are retained within an insulating housing.

This tool will make it easy to clean the male contacts one by one. You will also be able to avoid bending the contacts as you get that corrosion out. Then use a pin-like tool to clean the female contacts. The tool should fit without interfering with the structure of the holes.

When dealing with exposed contacts, you can use a micro brush soaked with a contact cleaner to remove the corrosion and/or carbon buildup.

Step 3: Spray Contact Cleaner

spray contact cleaner

Once you are satisfied that you have done a good job of scraping most of the corrosion or carbon buildup out of the contacts, you can go ahead and spray the contact cleaner.

Spray small amounts of the cleaner on all areas that need cleaning. We recommend using a contact cleaner that is safe on plastic when cleaning contacts that are retained within insulating housing. This way, you will not have to worry about any overspray damaging plastic housing.

When you choose to use conventional cleaning agents like nail polish remover, alcohol, or vinegar, make sure the product will not damage the contacts. This is a very important consideration to make when cleaning contacts that are gold-plated or silver-plated.

The plates are usually thin and could easily get damaged if you use a harsh cleaning solution.

Step 4: Allow the Contacts to Dry

After you have generously sprayed the contacts and removed all the dirt and corrosion. Allow them to dry up before you re-establish electrical connections. We recommend you let the contacts dry for about an hour, especially the ones that are retained within insulating housing.

FAQs

Can I use a mild agent to clean electrical contacts?

Yes, you can use a mild agent like vinegar and baking soda to clean contacts. But you should be more careful when rinsing it off. That’s why it is advisable to use a contact cleaner, which is specifically made for contacts and you don’t have to rinse it off after cleaning.

Is it safe to clean contacts while still connected to the power supply?

There will be some level of safety when using a contact cleaner with a high flashpoint and dielectric strength. But it is always recommended to disconnect the power supply before inspecting or cleaning your electrical contacts.

Should I be concerned about plastic insulating housing getting damaged?

There should be no reason to worry as long as you use a contact cleaner that is safe to use on plastic components and connectors. 

Takeaway

It isn’t hard to learn how to clean electrical contacts. You just need to get a high-quality contact cleaner that has a high flashpoint, it’s highly evaporative (leaving no residue behind), it’s free of water, doesn’t contain hazardous ingredients, and offers precision cleaning. Just make sure you always disconnect the power supply before starting any cleaning process.