Can A Bad Battery Cause A Check Engine Light To Come On
Problems caused by a bad/faulty Battery
If you have a bad or faulty battery then it can affect your engine’s computer. Any faulty electrical system in a car can play some tricky games, your cars battery is part of this electrical system.
A bad battery can make the whole electrical system act rather crazy.
If your car battery cannot provide the correct voltage stream that your car’s computer needs to function properly then a few things may happen; your check engine light may come on, your engine performance may drop, your transmission shifts may be a bit unusual if you drive an automatic, and your fuel economy may decline.
If your car’s battery is bad, then there are some easy fixes, but you may have other issues that limit the car battery from creating the appropriate amount of voltage.
So before you look into do anything to fix the battery you should check a few other things and also do a battery test on it.
Things you should do before you replace the car computer.
It may not be the fault of the battery, there may be other factors that are affecting the battery. These could be; a bad alternator, a bad voltage regulator, bad battery cables, or even corroded terminal connections.
If you check all these and they seem to be fine then you may need to replace the battery/ computer. But be sure to check these before you jump to the conclusion that it is solely a bad battery causing you problems.
Why else might your check engine light be on?
Your car’s check engine light may come on if it is time for a preventative maintenance service. If this is the case you will likely also see a service warning light. However, more often than not it is something else.
These are some of the main reasons why;
One of the least concerning reasons your check engine light may come on is if you haven’t tightened your gas cap enough. A loose gas cap will make a check engine warning light come on as there should be a vacuum seal with the cap when you have tightened it.
If it is loose, or cracked, or even broken, the check engine light will come on. This is one of the least concerning reasons your check engine light may come on.
One of the more concerning reasons your check engine light may come on is because your catalytic converter is going. The reason that this is of concern is that this can be very expensive to replace and your vehicle needs it to run.
This is part of the vehicle’s exhaust system, you may notice it is on its way out if you notice a rotten-egg smell as well as a check engine light. We hope it is not this, but it can be.
This is a crucial part of the car, this measures how much unburned oxygen is in your car’s exhaust, and if there is too little or too much, this may damage other parts of the engine.
A fault oxygen sensor will always provide a check engine warning. It is one of the most common reasons why this will come up when you are driving.
Mass airflow sensor
Similarly, the mass airflow sensor in the engine of your car measures the air coming into the engine to ensure that the right about of air mixes with fuel. If you are not getting enough/ a correct air/fuel mixture then your engine may stall or reuse to start.
When this part of your car fails, the check engine light will illuminate due to the onboard computer receiving a signal teat there is a problem with the air and fuel combination in the engine.
Finally, the last issue would be worn spark plugs, or the plug wires, which will result in a check engine warning. Just about anything wrong with the ignition system in the engine will likely cause this light to come on.
If you have done over 100,000 miles in your car and you have not had your plugs change, it is probably about new time for new plugs and new wires anyway. Stalls are yet another indication that there are issues with the spark plugs.
So it is a good idea to keep your eye on these things anyway.
Fixing the check engine light
Checking it works
How does the check engine light even work?
Well, the computer inside your car uses input signals from sensors that generate signals for fuel and spark delivery, for all the functions. The computer is constantly monitoring all input signals that could affect your emissions.
The computer will also determine if the problem meets the criteria for generating a code. Instead of identifying what has failed these codes refer to what part of the car is affected by the failure. This can make them confusing, but it proves just how intelligent the computer of your car is.
To avoid any issues with your car it is good to keep monitoring your car regularly, know your car, and ensure that everything is working well. If you are going to be taking a long trip then it is good to give your car a good once over beforehand.
If you do get a check engine light coming up, check other parts of your car first and run a battery test before you jump to the conclusion that it is a battery/ computer fault.
It is also useful to understand the codes that come up, if you know what part of the car is being affected you can use your knowledge to try and track down the source. If you can’t bear the thought of tackling the codes, then take your car to a mechanic who will help you solve the issue.
Most of the time the issue isn’t in the battery itself, but the battery may be suffering due to a fault elsewhere.