Car batteries supply current to the whole electric system of the car apart from doing the first and foremost, starting your car. You must know what happens when you connect a car battery backward to safeguard your vehicle and its components. Wrong connections will lead to unwanted situations both for you and your car.
Is Backward Connection a Problem in Car Batteries?
Yes, it is. The battery of your car powers the whole car with electricity. For this, you need to connect the positive terminal of the battery with the starter wire and the negative terminal of the battery to the engine block. If you alternate this connection, there will be complications.
Backward Connection of Car Battery | Problems and Complications
The list of trouble you will face if you connect a car battery backward is conditional. You will face car specific problems. Nevertheless, there are some general issues that occur in most vehicles when its battery is connected backward.
Car Will Not Start
Even if you don’t realize what you have done, your car will not start because of the wrong connection in your battery. No electricity in the starter and other parts means that your car does not have what it needs to get started.
Backward Current Flow
The direction of current flows matters a lot in devices having diodes. So a backward current flow in those devices, like the Engine Control Unit, will stop it from working and may even fry the device on the process. However, in some other electrical devices, the direction of current flow does not have an effect.
You are likely to see sparkles coming out from the connection as soon as you connect it backward. This is because the circuit that was supposed to be completed with the battery has now received wrong connections. So the battery will not accept the mismatch and react with sparkles.
Complex chemical substances inside the car battery will react differently to the backward connection. A series of chemical reactions will initiate the production of hydrogen. The acid inside the battery will also react and gas foams may arise from the battery. This will lead to the battery being completely dead.
Explosion and Fire
Backward current flow combined with the unexpected chemical reactions may cause the battery to explode. Trying to start the car may lead to this scenario. Additional fire after an explosion has occurred in the past with car batteries.
As a safety measure to protect your car’s electrical parts, the fuse will blow. It acts as a circuit breaker. If a current of high magnitude, supposedly harmful to your car, tries to flow from the wrongly connected battery, the fuse will go off and prevent further current flow. It’s a way to protect your car’s parts.
What to Do After You Have Connected a Car Battery Backwards
You have two options here. You can either call a professional mechanic to check your car from head to toe or, you can take a little risk and inspect the type of damage that has been caused by yourself. If it’s nothing significant, say, the fuse went off, then you can simply buy and replace the fuse.
Frequently Asked Questions
Q: Do I need to change the battery after connecting it backward?
Ans: Depending on your car, the damage to your battery could be very high or very low. If it’s high, then you have no other options but to replace it with a new one.
Q: Can cars run on batteries connected backward?
Ans: Very old cars, which have positive earth, could actually start and run fine. But most cars today have a negative earth which doesn’t let the car run or start if it has a battery connected backward.
The answer to what happens when you connect a car battery backward is often very disappointing to the car owners. You should always double-check your battery connection. Regardless of how protective your car looks like, there is always something that could go wrong. So never connect your car battery backward.