How to Fix the Positive Battery Terminal That Is Hot- Easy Fix

Positive battery terminal plays a vital role in cars since it is a three-piece. It connects from battery to the starter, megafuse to the alternator, and then from the starter to the megafuse. This implies that if anything happens to the three components, the positive terminal is likely to get hot.

For more of such educational information, I would urge you to continue reading our paper. We have decorated it with necessary content like causes of positive battery terminal hot problems and useful solutions. You won’t be the same person after going through this article.

Additionally, you should expect to come across various tips that will make your battery more convenient. We will also equip you with reliable information frequently asked in the questions section. You should therefore allow me to take you through this journey till the end.

Causes of Positive battery terminal hot problem

Causes of Positive battery terminal hot problem

Without wasting much time on the introductory part, let’s go straight and see the common culprits for this problem. Have a look on these determinants;

1. Loose connection

Loose connection can be the real culprit to be held responsible for hot positive battery terminal complication. Maybe the nut that secures the red positive wires on firm/good contact with your battery’s terminal connection bolt isn’t tight enough. When this complication is combined with the high electricity flow the vehicle is draining, the terminal will get hot.

2. Broken wire in the cable

Another culprit that you should take into consideration is the faulty wires in the cables. When the cables get hot, the terminal will have no otherwise but get hot since it will be struggling to pump required energy. Operating with broken wires is famous for causing resistance too.

Such a complication will make the red wire copper massless for the necessary amount of power through the cables. Knowing the location of the problem is always the best idea to know the best solution.

I thought you should know that all wires and clamps are made of copper metal, meaning that heat will be experienced immediately from the cables to the positive terminal. The positive terminal will automatically become hot.

3. Bad connection

Another cause for the hot positive battery terminal is the poor connection. This issue happens mostly when cranking, the wires get hot at specific points. If you doubt this could be the challenge, observe if all the electric components in the vehicle go off when you start the engine. Your connection is faulty; maybe something bad has happened to your connection.

4. Corrosion in the terminal

Corrosion can result in a hot positive battery terminal when it occurs in the insulation. This problem implies that the terminal won’t operate appropriately as a result of corrosion buildup. Any kind of corrosion will eventually give rise to resistance which is a threat to the normal functioning of the battery.

The entire electricity flow will be affected, reducing the speed flow; the terminal will automatically get hot.  The issue might not be felt at instant, but after a few months or days, corrosion will start eating the lead terminal. Remember, corroded positive battery terminals will make the engine take a prolonged period to start.

5. Defective starter

Since one of the pieces of the positive battery terminal also connects to the starter, anything bad with the starter implies that the terminal will have to misbehave. This problem is exactly what we refer to as the hot positive battery terminal. The engine won’t turn over, but the terminal continues to get hot.

The starter is likely to be broken or the red wire to the starter is shorted. This complication tends to trigger excess current flow from your battery, heating up the terminals.

6. Faulty alternator

The alternator can become problematic after an extended period in service. Maybe you should consider determining the age of your alternator and if you find that it is 2 or more years old, replace it. Many cranks will therefore exert excess pressure on the terminal. The motor will always spin while you start the engine.

7. Oxidation in the table

The corroded red wire is popular for developing resistance, overheating the positive battery terminal. The heat will then be transferred from the complicated cable to the positive terminal of your battery. Heat is therefore transferred directly from the problematic cable to the battery that will eventually heat the terminals.

These cables are made of rubber and copper materials for remarkable performance. After cranking the engine for an extended period, the rubber will slowly deteriorate, cracking the cables.  Water will therefore find its way in the cable easily oxidizing the copper wires.

How to fix hot positive battery terminal problem

positive battery terminal hot

All the above complications are fixable with the help of the following actions. Determine the exact problem and then choose a necessary way to go;

Solution 1: Thorough cleanliness

There are a lot of parts that require cleanliness on your battery terminal. Under this action, you are required to make sure every component of the terminal or red wire is free from any kind of dirt. The dirt I am talking about is the corrosion buildup. All the connections should therefore be cleaned as well as the grounds.

The best tool to use here is the sandpaper for scrubbing the terminal surface of your battery. For instance, you can decide to make a harness running from the battery to starter and from the starter to alternator using reliable 4 gauge wire. Additionally, place a fine ANL style fuse in line with the holder; life will be good.

Cleaning also involves getting rid of all the accumulated grease from the fuse box that might have stuck there for several years. Grind the entire connectors with the help of a grinding paper before assembling.

Solution 2: Tightening the nut

For a loose connection problem, the solution is straightforward as you only have to make sure the nut holding the red wire in the terminal is tight. You can achieve this with the help of a screwdriver and two wrenches. You have to ensure the bolted connection wraps tightly around the positive battery terminal.

Doing so is necessary as you will be curbing sparks that could lead to melting of the terminal. Besides the overheating positive battery terminal problem will be over. Clamp the nuts to enhance secure connection.

Solution 3: Replacements

There might be several components that call for substitutes like the alternator, cable, the starter etc. If either of the components has served you for more than three years, then this might be the right time to opt for a replacement. Some of these items start to misbehave due to aging, check the lifespan of these connectors to make sure they are healthy.

There are various models of battery cables in the market that can serve you well.

Solution 4: Inspect the battery for leakage

Electrolyte leakage can be another solution for your hot positive battery terminal complication. Electrolyte leakage automatically renders the battery useless and therefore you have to contain the issue by tightening the openers. If the battery has cracks, then I would suggest buying a new one or find an expert to seal the broken part.

Solution 5: Measuring the alternator

Here, you are required to use a multimeter to determine the usability of this component. If the multimeter reads something from 13.40V – 13.55V, this is a clear indication that the item is still in good working condition. However, if it reads below that, then you might be forced to look for a new alternator for a replacement.  

Tips for betterment

Tips for betterment
  • Before you start to clean the red/positive battery terminal, remember to disconnect the wire end from the current lead.
  • Choosing a suitable ring diameter is always necessary since it improves contact.
  • Cleaning the terminals of your car battery is always advisable after a period of something like 3 months. Doing so will curb corrosion buildup and correct loose connection problems.
  • Check the condition of the cables regularly to ensure the cable doesn’t rub through the insulation that will eventually short out to the engine or frame.
  • Positive battery terminal is a three-piece component connecting megafuse to the alternator, starter to the megafuse, and battery to the starter. If any of these connectors is problematic, the battery terminal will overheat.


  • What are the indicators for broken battery cables?

Some of the symptoms of a defective battery terminal are;

  1. The interior lighting of your car  will dim
  2. The engine takes long time to crank
  3. Sometimes the engine may completely fail to crank
  4. The vehicle lose electricity
  5. You may hear clicking sounds when you turn the key.
  6. More so, the engine may stall if it stagnates for a long period.
  • Will a defective battery terminal drain my battery?

Not really, loose connection only tends to hinder the battery from charging. This situation looks as if the battery is being drained.

Final words

Bad contact remains one of the indicators to inform the car owner to pay much attention. Handling the above problems on time will prevent the situation from worsening. Positive battery terminal serves a critical role, meaning that you should take care of it.

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