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My Car Won't Start But The Lights Come On

It's really annoying if your car won't start. Even though the radio, dashboard lights, overhead, and interior were all on, so what really happened? You know this has to do with power. You start to think, is there a problem with the battery or alternator? Well, if this is what you experience, we will guide you to find a solution!

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In this case, you actually get power because when you try to engage the starter, you will hear the starter try to turn the motor.

But, it's like a loss of power coming from the battery to the starter to turn the engine. 

Usually, there is also a warning "battery charging system service," which indicates something is wrong with your battery or alternator.

Check Battery Terminal

So the first thing you want to do is check the actual battery terminal. If it is dirty, you have to clean it. Don't forget, you are dealing with a power source. So, typically you would pull the negative side off before going to the positive side. You know, when you mess up the positive-side and then hit bare metal or fenders, then it's going to give you shocks or sparks, so keep safety first.

The accumulation of dirt that sticks to it can cause the voltage to the starter to decrease. So you have to clean up everything, you can use a liquid cleaner such as WD-40 rust removal, dry it, and then reassemble the cables and fasten it, do not let loose.

Check Battery Voltage

Then try to start the engine again. Some vehicle models have a battery voltage indicator light, so you can see what the actual voltage is.

The standard voltage for a car battery is around 12.6 V. So, if you find it lower than that value, your car will probably fail to start.

If your car still doesn't start, then you should check the battery voltage more closely.

You know, the battery voltage indicator on the dashboard sometimes doesn't show the real value, meaning it could be higher or lower than the stated figures.

Therefore, you need another tool to measure battery voltage accurately, you can use a multimeter, don't worry because the price is relatively low.

multimeter


Before measuring the battery voltage, you should set the multimeter to DC V at 15 or 20 volts. Then stick the positive and negative sides to the battery and check what the actual voltage of your battery is.

You may find a significant difference with the results shown from the battery voltage on the dashboard, but just use the values from the multimeter as a reference.

Check Alternator Voltage

Even though you know that your battery voltage is low, you also need to check the alternator. That way, you will also understand how much voltage the alternator produces back to the battery because when the engine is running, the alternator should recharge the battery.

Remember, if you rush to the conclusion that the problem is with the battery and it turns out that the damage is actually with the alternator, then you will probably spend over $ 100 on a new battery that you really don't need.

So the question is always, is it a bad battery or alternator?

To find out whether your alternator is good or not, you have to jump-start from other vehicles. 
As soon as the engine starts at jump-start, you want to know if the battery voltage increases. When you jump-start, turn on all accessories such as headlights, AC, radio, overlights, so that you don't over-charging that will damage the battery. 

The charges coming to the alternator back to the battery it should read 14 - 14.7 V while the figures at 12-13 V will not recharge the battery. 

You can use the multimeter again to check it. 

Conclusion

If the battery voltage shows 14 - 14.7, then there is no problem with the alternator, but you know something is wrong with your battery, so you need to replace it. And vice versa, if the battery voltage remains low during jump-start, it is confirmed that the alternator is damaged.
Ryan Daniel
Ryan Daniel Ryan Daniel is a car enthusiast. Since owning his first BMW at a young age, he has loved the automotive world even more.