An Electrical System is an important part of any car. There are a large number of separate components in the electrical system of your car. These components control the equipment in your car; like electrically operated windows and side mirrors to starting the engine and charging your portable devices.

These functions depend on the health of the electrical systems. A catastrophic failure in the electrical system will stop your car in its track. 

Troubleshooting electrical problems can be an exasperating task, but it does not have to be so if you keep a few simple rules in mind: Every electrical circuit needs a power source and most electrical devices require a minimum voltage to function properly and they must have proper continuity of its circuit.

Knowledge of these two factors can help you diagnose the fault. All you need to check if there is the required voltage in the circuit and secondly if there is excessive resistance or a loss of continuity.


Sometimes it can be quite difficult to pinpoint what the electrical issue is, but if you or your technician is adept in understanding the symptoms then the fault can be found in no time.

Here are some common electrical problems that you might face that you can diagnose yourself and possibly resolve them. However, if the problem is complex then a qualified technician has to see the fault and repair it.


A blown fuse can shut down your electrical functions like headlights, signals, electric windows, or even stop the car completely.  It all depends on which fuse has blown and why.

Fuses are there to protect the electrical devices and wiring from excessive current flow. If a fuse has blown it means there is something wrong with an electrical system or its wiring. 

In a modern car, most of the relays and fuses are grouped inside one or two boxes called the power center. Some cars have two or more fuse panels inside the vehicle, for lower power electrical accessories such as dashcam, radio, audio system, windows, USB slots, horn, interior lights, etc. 

The easiest way to check a circuit fuse is to bypass it with a jumper wire. When you bypass the fuse, if the circuit works, then you have found the problem. Replace the fuse. 

It is a simple process to pull out the fuse using a pair of tweezers and replace it with an equivalent fuse. The replacement fuse must have the same current rating as the original one.


Often the car’s battery cables are a source of trouble. It is the cable that connects the battery to the alternator and the entire electrical system of your car. Check if they are loose; if so tighten them with a spanner. 

There is a good chance that there is corrosion deposit on its terminal, In this case:

  1. Remove the terminals from the battery and clean them with a damp cloth, if you have sandpaper slightly rub over the battery terminals and the inside of the connectors to have a clean contact.
  2. Now install the connector back and tighten them fully using an adjustable spanner. See if this works.


If the cables are alright then maybe you have a dead battery on your hands. Car batteries normally last for 2-3 years or so depending on your driving habits.

To check your battery’s state of charge, check the voltage with a voltmeter. It should read 12.4 volts or higher. If the battery voltage is low, it should be recharged and tested. 

Read More: How To Tell If a Car Battery Is Bad


A more serious issue may be that you have a bad alternator. Your car alternator charges your battery and powers your electrical system while the engine is running.

The alternator is vital to the car operation as a bad alternator will prevent the battery from recharging. A simple indication that you have a bad alternator is that your headlights appear dimmed at night when driving.

You’ll also notice some of your car’s accessories like the radio will not work and the interior lights will appear dim. Low alternator output can be caused by a slipping drive belt, one or more defective diodes in the alternator’s rectifier assembly, or a defective voltage regulator.

It can also be caused by a broken drive belt, loose, broken or corroded wiring connections, and failures within the alternator.

If your car lights are flickering, its most likely due to a faulty alternator, you can read more here: Why Car Lights Flicker And How To Fix It


If your car is lurching, missing, or idling rough, you may have a loose or dirty spark plug that should be checked. If the spark plug wires are not in a good condition, they are wet, cracked, burned, or have high internal resistance exceeding the specifications, then they can interfere with good spark production and make the engine difficult to start. In such a situation the spark plugs need to be cleaned or replaced.

Read More: Why Does My Car Turn Off While Driving?


Low voltage is usually caused by poor connections or improper grounding networks which causes the voltage to drop below what it should be at. If the wires are worn out and corroded and will require replacing to work effectively again.


Ground circuit problems are bad for car electronics. If the grounding cable connection becomes bad, it causes the voltage levels to drop. Wires get loose due to heat, insulation becomes weak, their life is shortened, or the vibrations from everyday driving and can lead to various problems.

The metallic body of your car acts as the ‘ground’ and is required to connect each part of your car’s system to the battery. Each of these components is connected by the grounding system.

Check the vehicle’s wires and connectors and tighten to help resolve the problem, or cleaning them can assist in solving many grounding issues.


A bad starter motor can be caused by improper or lack of maintenance or even regular wear and tear. The car’s engine will not crank and the car won’t start without a good working starter motor.

There can be many starter motor problems; from slow-cranking of the engine to no-cranking at all. This can be as a result of bad electrical connections or an undercharged or failed battery. 

Maybe the starter motor has problems of its own, like worn brushes which are carbon pads inside the motor that supplies power to the rotating armature.

It may have a short circuit or an open circuit in the armature or the field coils, or it may be due to damaged bushings. This needs to be looked at by a mechanic. 


In modern cars with push-button start system, a bad Start Button or a bad Smart Key Fob may be the reason if nothing happens when you push the Start button, the battery in your key fob may be dead, or the fob may be defective, or there may be a problem with the push button circuit. 

In some cars, you may place the fob near the push start button, or press the start button with the fob, or by inserting the fob into a designated slot on the steering column may allow it to communicate with the ignition system so your engine will crank and start.


The dashboard display requires accurate information from vehicle sensors so that they can be displayed correctly. 

The speedometer, fuel level indicator, oil pressure, and temperature sensors cannot function properly if there is a problem with the respective sensor or its wiring loop. 

If all displays seem to work correctly except for one gauge then there is a chance that its sensor or wiring is bad. If one or more gauge display does not show up, or there is a flicker in all the displays then the problem is likely in the instrument panel itself. This needs to be checked by a car electrician.


The headlights are a very important and essential safety system for nighttime driving & visibility. If your headlights are not working properly, or are not aligned properly, you will not be able to see the road clearly. This is dangerous.

The headlight bulbs housing is made of a sealed plastic shell with the bulb and socket mounted on the back. Remove the socket from the headlight housing, then you can easily pull the old bulb out of the socket and replace it with a new one.

It must be the same size and style as the original bulb. For sealed headlamps, the entire assembly has to be replaced.


We have discussed the major electrical problems that you may encounter in your car. Many of these problems are easy enough to be solved by yourself.

However, some of them are quite complex and require an expert to repair them. Even if you cannot repair the fault yourself, the diagnosis will be useful to the technician who will eventually repair the fault.

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