Why did my dashboard lights go out while driving

If you’re driving down the road and all of a sudden your dash lights come on, it can be confusing and even scary. But don’t worry – in most cases, it’s not as serious as it looks. 

All of your dash lights could come on while driving due to a number of reasons but the most likely scenario is that your vehicle has some sort of electrical issue. These can range from faulty wiring, battery problems, alternator problems, or a simple short circuit. 

Most cars and trucks have a system of dash lights that come on when a certain engine or vehicle conditions are met.

For example, if your oil pressure is low, the corresponding warning light will come on to let you know. These warning lights are usually red or orange, and they’re located in the center of the dash near the speedometer.

6 Common Causes of All the Dash Lights Coming On

There are a few common reasons why this might happen, so it’s essential to be aware of them. Here are some of the most common causes of dash lights coming on suddenly:

1. Battery Problems

One of the most common reasons for all the lights on your dash to come on is a problem with your battery. A dead or dying battery can cause problems with your car’s electrical system, which in turn can trigger all the lights on your dash to come on. 

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If the battery terminals are loose or corroded, it can cause a drop in voltage that will trigger the dash lights to come on.

The Tools You Will Need

• Wire brush
• Baking soda
• Socket wrench set
• Voltmeter
• New battery

How to Fix the Battery

1. Check the Terminals: If you think your battery may be the problem, the first thing you should do is check the terminals to see if they’re loose or corroded. If they are, you can try cleaning them with a wire brush and some baking soda. 
2. Disconnect the Nuts and the Terminals: Loosen the nuts that hold the battery terminals in place. Then, disconnect the negative terminal (black) first, followed by the positive terminal (red).
3. Clean the Terminals: Use the wire brush to remove any corrosion from the terminals. Once they’re clean, you can reconnect the terminals and see if that solves the problem. If not, you may need to replace your battery.
4. Use a Voltmeter: A voltmeter can also be used to test the battery’s voltage. If it’s below 12 volts, the battery is most likely the culprit. At that point replacing the battery is the best course of action.

2. Alternator Issues

All the lights on your dash may also come on if there’s a problem with the alternator. The alternator is what provides power to your car’s battery and electrical system when the engine is running. 

Failure of the alternator can cause all sorts of problems, including triggering all the lights on your dash to come on. Fortunately, diagnosing and replacing an alternator is usually a relatively simple and affordable process.

The Tools You Will Need

To replace your car’s alternator, you’ll need:

• New Alternator
• Automotive battery charger
• Ratchet and socket set

How to Replace the Alternator

1. Disconnect the negative terminal of your car’s battery. This will help prevent any electrical shorts while you’re working on the alternator.
2. Remove the serpentine belt. This can be done by loosening the tension pulley and then sliding the belt off of the alternator pulley.
3. Disconnect the electrical wires from the back of the alternator. There should be two or three wires connected to the back of the alternator. Use a socket wrench to loosen the bolts that hold these wires in place, and then gently disconnect them from the terminals.
4. Remove the mounting bolts that hold the alternator in place. In most cases, there will be four bolts holding the alternator in place. Use a socket wrench to remove these bolts and then lift the old alternator out of the engine compartment.
5. Install the new alternator in the reverse order of removal. Be sure to torque the mounting bolts to the proper specification, and then reconnect the electrical wires.
6. Reinstall the serpentine belt, and then tighten the tension pulley.
7. Reconnect the negative terminal of your car’s battery.
8. Start the engine and let it idle for a few minutes. Check all of the electrical components in your car to make sure they’re working properly.

3. Loose or Damaged Wiring

Loose or damaged wiring can cause a number of electrical problems, including dashboard lights malfunction.  This can occur for a number of reasons, such as after an accident or due to age and wear and tear. 

If you live near a farm, there is also a high likelihood that pesky rodents have chewed through your car’s wiring; talk about a high-energy diet.

Replacing car wiring is a challenging task, especially if one of the cable packs has been damaged. You can swap the battery clamps with relative ease but for everything else, it’s best to hire a professional car electrician. 

4. Faulty Steering Wheel Positioning Sensor

The steering angle sensor is what tells your car’s computer how far the steering wheel is turned. This information is used to adjust the car’s headlights, as well as for stability control and traction control systems. 

A faulty steering angle sensor can cause all sorts of problems, including triggering the lights on your dash to come on. Unfortunately, diagnosing and replacing a steering angle sensor can be a bit of a challenge.

Therefore, taking your vehicle to a qualified mechanic or dealership for diagnosis and repair is the best course of action.

5. ECU Problems

The ECU is a common culprit when it comes to all the dash lights turning on. There are a few things that can cause ECU and dash light problems. One is a bad connection between the ECU and the dash light. Another is a problem with the ECU itself.

If you suspect the ECU causing all of your dash lights to come on, the first thing to do is check the connections between the ECU and the dash light.

Make sure that they are tight and that there is no corrosion on them. If the connections are good, then the next step is to check the ECU itself.

The best way to test the ECU is to take it to a mechanic and have them test it since the chance of misdiagnosing a problem is rather high. However, you can rather easily replace the ECU by yourself. You can buy a new one online or at a local auto parts store.

Here’s a good video on how to test the ECU: 

Tools You Will Need

• Screwdriver
• Ratchet and socket set
• Replacement ECU

How to Replace the ECU

1. Disconnect the negative battery terminal to prevent any electrical shorts.
2. Locate the ECU. It is usually located under the dash on the driver’s side.
3. Unplug the connectors from the ECU. 
4. Remove the screws or bolts that hold the ECU in place.
5. Install the new ECU in the reverse order of removal.
6. Reconnect the negative battery terminal.
7. Start the car and test all the lights to make sure they are working properly.

6. Electrical System Problem

Another common cause of dash lights coming on is an electrical system problem. This can be caused by a number of things, such as a problem with the fuse box or a short circuit.

The fuse box is responsible for supplying power to all the electrical components in your car, and if there is a problem with it, it can cause all sorts of issues, including dash lights coming on. 

A short circuit is another common electrical issue that can cause the dash lights to come on by generating an electrical current to flow through the wrong path. Checking the fuse and relays is a rather easy process.

Tools You Will Need

• Test light or multimeter
• Screwdriver (to remove the fuse panel cover)
• Flashlight (to help you see inside the fuse panel)
• Replacement fuse

How to Check the Fuses & Relays

1. Check the Fuse Box: To check the fuses in your car, first find the fuse box. This is usually located under the hood, but it may also be located in the trunk or under the seats. 
2. Take a Look at the Fuse Diagram: Once you’ve found the fuse box, open it up and take a look at the fuse diagram to identify which fuse belongs to which circuit.
3. Check If the Fuse Is Blown: Use a test light or voltmeter to test each fuse to see if it is blown. A blown fuse will show no continuity between the two terminals. If a fuse is blown, replace it with a new one of the same amperage.
4. Use a Multimeter: Finally, if you suspect that a relay may be faulty, test it using a multimeter. Set the multimeter to the Ohms setting and check for continuity between the two terminals. If there is no continuity, the relay is likely defective and should be replaced.

FAQs

Do the Dash Lights Turn On When You Start Your Car?

Don’t confuse all of your dash lights turning on while starting the car with a problem. Many times when you first turn on your vehicle, all the lights on the dash will light up as a self-check.

Usually, if there’s no problem, they will go off after a few seconds. However, if any of the lights stay on after starting the car, it’s an indication that there may be a problem.

What Do Dash Lights Mean?

Dash lights are used to provide information to the driver about the status of the vehicle. They can indicate anything from a low oil level to a problem with the brakes.

Why Are My Dash Lights Not Working?

There are several possible reasons why your dash lights may not be working. First, check to make sure that all of the bulbs within the dash are intact (if your vehicle uses such, and not a screen, for example) and screwed in securely.

If they appear to be fine, then the issue may be with the fuse that powers the dash lights. Try replacing the fuse and see if that solves the problem.

My Dash Light Is on, But It’s Very Dim. What Does This Mean?

This could indicate a problem with the electrical system of the vehicle. Try replacing the fuse that powers the dash lights to see if that solves the problem. If not, then you may need to take your vehicle to a mechanic or dealership for further diagnosis.

One of My Dash Lights Is Flashing; What Does This Mean?

A flashing dash light usually indicates a more serious problem than a solid light. It is important to try and identify which dash light is flashing, as this will give you a better idea of what the problem may be.

Once you have identified the flashing light, consult your owner’s manual or a mechanic to find out what it means and how to fix it.

I Have a Warning Light on My Dash, but I’m Not Sure What It Means. What Should I Do?

There are many different types of warning lights that can appear on a dash, so it is difficult to give a definitive answer without knowing which specific light you are referring to.

However, in general, it is always a good idea to consult your owner’s manual or a mechanic whenever you see a warning light on your dash. This will help ensure that you take the appropriate steps to fix the problem and avoid any further damage to your vehicle.

Conclusion

It’s not common for all the dash lights to turn on at the same time; Usually, a light or two will show up to warn you of a certain problem. Should all of them turn on as you’re driving, the issue is most likely of electrical nature. 

The symptoms could be tied to the battery, alternator, or wiring. Follow our steps to identify the cause and then repair it. Electrical issues are not the easiest to fix, and getting some help from a professional car electrician is advised. 

Here are some articles that might interest you:

Dashboard Light Stays on When Car Is off (Common Causes)

How Do You Dim Dashboard Lights in a Toyota Highlander?

What Causes Brake Light On Dash To Stay On?