Push Button Start Malfunction in Mazda 3: Diagnosing and Fixing

The Mazda 3 comes with a push button start that makes starting your car more convenient. You no longer have to wrestle with getting the key in the ignition. Starting your car is as easy as pushing a button. But what happens when your Mazda displays "Push button start malfunction" on the dashboard?

What causes the push button start malfunction in the Mazda 3? The issue is usually caused by an electrical issue with a component of the ignition system. This could be the low system voltage or a damaged body control module. It could also be a result of a dead key fob battery.

What Causes a Push Button Start Malfunction?

There are three major causes of a push button start malfunction in a Mazda 3. All of these issues are caused by an electrical issue with part of the ignition system. Knowing what could go wrong with the system is the first step in diagnosing and solving the problem.

Here are the problems that can cause the "Push button start malfunction" warning to appear on your Mazda's dashboard display.

• Low Battery in the Car

The most common cause of the push button start malfunction is a dying or drained battery. When the system voltage in the car is too low, it can result in different error messages. When the battery is too low, the engine won't crank. The push button malfunction warning will appear as a result.

This commonly occurs in the Mazda 3 when the car has been left without running for too long. The car has a sensor that detects the key fob. When the key fob is stored near the car, they will continue to communicate with each other, which drains the battery. Normally this doesn't cause any problems, but if the battery is weak, or the car is left without being driven for too long, this can cause the battery to die.

• Low Battery in Key Fob

The keyless start in your Mazda won't engage if it can't detect that your key fob is inside the car. The key fob emits a signal that the car recognizes to identify when the fob is in the car. When the battery in your key fob is dead, it won't be able to emit this signal, and the car won't start. I've written an article about the keyless system malfunction message - have a look.

• Faulty Body Control Module

The Body Control Module (BCM) in your car is an electronic component that acts as a supporting computer. It controls the electronic systems that aren't directly related to the engine, like seat controls, wipers, lights, and the push button system.

By the way, you may also want to read this articel telling you about the ghost touch problem of the infotainment screen - a very common issue in Mazda 3.

How Do You Diagnose Push Button Start Malfunction?

When the message appears, the dashboard will also instruct you to have the vehicle inspected. If you know the causes of the problem, and how to diagnose it, then you'll be able to handle that step yourself.

Let's look at how to diagnose the common problems that cause the push button start malfunction in the Mazda 3.

1) Look for a Check Engine Light

When the battery gets too low in a Mazda, the check engine light will come on. This lets you know that the battery is low so you can get it checked on time. If the check engine light is on at the same time as the push button start malfunction error, then there is a good chance that the problem is your battery.

You can diagnose this by jump-starting the car or trying to start the car with another battery. If the car works, then the problem is a drained battery.

2) Press the Key Fob against the Push Start Button

This bypasses the key fob battery and starts the car directly. If the problem is a dead key fob battery, then the car should start. If the car still refuses to start, then the problem isn't the key fob.

3) Observe for Other Electronic Faults

If the BCM is faulty, you may notice other electronics in the car are failing or malfunctioning. Some of the symptoms of a faulty BCM are similar to the signs of a failing battery. You might notice some of the car's electronic systems are malfunctioning.

Ensure that the battery is in good working order. If you have made sure that the battery is in good condition, but the car's electronic systems are still malfunctioning, then you probably have a faulty BCM.

Some systems that you might notice malfunctioning are:

• The door locks
• The headlights
• Wipers
• Horn
• Power windows
• Seat Controls

How Do You Fix a Push Button Start Malfunction?

Once you have diagnosed the cause of the malfunction, you'll be ready to fix the problem. Most of the time, the solution is as simple as charging or replacing a battery, though you may need to replace the BCM in more extreme cases.

Here are the ways to fix the push button start malfunction error in your Mazda 3.

1) Charge or Replace the Car Battery

If the problem is with the battery, you should first attempt to charge it. You can do this by running jump-starting your car and running the engine for about thirty minutes. This should charge the battery enough for it to start itself and keep running normally.

If charging the battery doesn't work, then you probably have a weak or bad battery. If this is the case, you'll need to remove the bad battery and install a new replacement.

2) Replace the Key Fob Battery

The key fob battery is not rechargeable, so it will need to be replaced once it no longer has a charge. You can easily replace the battery yourself.

If the key fob is damaged or faulty, you will need to replace it. You can get a replacement key fob at a Mazda dealership.

3) Replace the Body Control Module

If you have confirmed that you have a faulty BCM, then it will need to be replaced. It is easiest to have the BCM replaced at a dealership because the BCM needs to be programmed after replacement.

If you're capable of removing the interior paneling of your Mazda 3 and reprogramming the BCM, then you can make the replacement yourself. You can also replace the BCM yourself and have it programmed at a Mazda dealership.

When you have removed the BCM, you should examine it for corroded or damaged electrical connectors, which can be repaired without needing to replace the module.

How to Prevent the Push Button Start Malfunction from Appearing

Once you've fixed the malfunction, it's important to know how to prevent it from coming back. This way you won't have to deal with the downtime of waiting of looking for a battery to jumpstart your car and having to wait for your battery to charge.

Let's take a look at some of the ways to prevent the push button start malfunction from occurring in your Mazda 3.

• Store Your Key Away from the Car

If the key fob is stored too close to the car, it won't allow the sensor in the car to turn off. This keeps the car's computer running which drains the battery over time.

To prevent this, you should try to store the key more than five meters away from the car. This keeps the key fob outside of the sensor's range so they won't be able to communicate.

If you can't keep the key five meters away from the car, another option is to store the key in a faraday bag. This is a small bag that prevents electromagnetic waves from reaching its contents. A faraday bag will keep the key and the car from communicating by interrupting the signals between them.

• Don't Leave the Car for Too Long

Allowing the car to sit in one place for too long can cause the battery to develop deposits that weaken it and shorten its lifespan. If you have the option, you can run your engine for a few minutes every few days, even if you don't need to take it anywhere.

If you need to travel or go on vacation, you should disconnect your battery from the car and store it in a cool, dry location. This prevents the battery from draining and keeps it in good health until you return.

Conclusion

The push button start malfunction is an annoying issue that stops you from starting your car when you need it. It is usually a result of a drained car battery, a dead key fob battery, or a faulty BCM.

Diagnosing the issue requires testing the battery to find out if it is drained or bad, and testing whether the push button start works when you bypass the key fob battery. If the push button start doesn't work, and other electronic systems in the car are malfunctioning, then you probably have a bad BCM.

Fixing the problem is as simple as charging the car battery or replacing the faulty part. Once you've taken the necessary steps to fixing the problem, the error should disappear, and you'll be back to driving again.