The Instrument Panel: Your Guide to Car Dashboard Lights

The portion of the dashboard which sits directly behind the steering wheel is called the instrument panel. This panel houses various gauges and lights which provide the driver with important information about the status of the vehicle. It is essential to know your way around your vehicle’s instrument panel, as misunderstanding or overlooking something could result in enormous inconvenience, for instance, if you were to run out of fuel and break down by the roadside. More importantly, ignoring lights on the vehicle’s instrument panel could put you and your passengers in danger! If there is a problem with the engine, a door is not properly secured or your tire pressure is low, the instrument panel should warn you.

While driving, you will need to glance at the gauges on the instrument panel regularly. Many of these gauges – including the fuel gauge, speedometer and tachometer – provide the driver with information that will help them decide when and how to alter course, speed or otherwise change their driving behavior. Let’s check out some of the most common instrument panel gauges.

Tachometer

The tachometer displays the rotation of the engine’s crankshaft, in revolutions per minute (RPM). In some vehicles, the tachometer is an analog dial, while in others it is displayed digitally. Usually, the numbers on the dial range from one to seven – though this may differ on some vehicles.

The tachometer’s job is to help the driver of a manual vehicle select the right gear for current driving conditions. Though every vehicle is different, most driving experts recommend shifting up a gear when the tachometer reads around “3” (3,000 RPM) and shifting down a gear when it reads around “1” (1,000 RPM). Automatic transmission vehicles generally have tachometers too, though monitoring the car’s RPM is not important unless you have temporarily switched to a manual driving mode.

Towards the top end of the tachometer dial, you will probably notice a section marked in red; this is the “danger zone”. If the tachometer needle is in the red danger zone for too long, or too frequently, the engine could overheat or become prematurely worn out.

Speedometer

The speedometer has a prominent position on the vehicle’s instrument panel, to the left or right side of the tachometer. This gauge shows your car’s current speed, in miles and kilometers per hour (mph/kph). The numbers on your speedometer may go up to 140 or 160 mph but this is because most car manufacturers produce standard speedometer dials to suit both low-performance and high-performance vehicles. In reality, your car’s top speed is likely to be somewhere around the 100-mph mark.

Get in the habit of glancing at your speedometer regularly while driving. This is particularly important when upcoming changes in roadway conditions may warrant a reduction in speed. If you are traveling at 35 mph while approaching a 20-mph school zone, you must plan ahead to give yourself enough time to slow down.

Odometer

The odometer can usually be found near the speedometer on the instrument panel. This gauge will tell you the total number of miles the vehicle has traveled since it has been on the road. While the main odometer cannot be reset, many modern vehicles also have a separate odometer which can be set back to zero, to measure miles traveled and fuel used during a specific trip.

The information provided by the odometer will help you to keep your car in good working order. Most vehicles need an oil change about every 3,000 miles and a service around every 10,000 miles. The vehicle owner’s manual should tell you how regularly your car will need an oil change and a service.

Fuel gauge

This gauge shows you how much gas is left in the vehicle’s fuel tank. Bear in mind that the fuel gauge only works when the engine is running. Towards the bottom end of the fuel gauge dial, you should notice a red section. Top up the gas tank immediately if the needle enters this lower end of the gauge, as it indicates that your fuel level is dangerously low.

To keep your vehicle in good condition, you should aim to keep the fuel tank at least a quarter full, topping it up before it drops below this mark. Persistently low fuel levels can cause problems with the fuel pump and fuel filter in any car, though it is a particular problem in older vehicles. If your car is more than 15 to 20 years old and has a metal fuel tank, allowing the gas to run low could cause a build-up of sediment in the bottom of the tank. This could clog fuel lines, block the fuel filter and ultimately, damage the engine.

Temperature gauge

Your vehicle may have a temperature gauge that indicates the temperature of the engine. If not, it will at least have an engine temperature warning light which will activate should the engine temperature rise to a dangerous level. Most modern vehicles do not have problems with engine overheating, so many manufacturers have chosen to scrap the temperature gauge in favor of a single warning light.

If your engine temperature warning light comes on, or the temperature gauge moves into the red “HOT” zone, do not continue to drive the car. Instead, pull over at the next safe opportunity and allow the engine to cool down. It may be that your engine coolant levels need topping up, but you should not check this until the engine has completely cooled down. Taking off the radiator cap while the engine is hot could result in you being sprayed with boiling hot coolant.

You may be able to cool an overheated engine by stopping the car, shifting into neutral and lightly pressing the gas pedal to rev the engine. Turning off the air con will also help, as this system places additional strain on the engine. If possible, switch the in-car heating on. While it may seem counter-intuitive, running the heating will ease the situation by drawing heat away from the engine and into the passenger compartment.

Turn signal indicators

When one of your turn signals is active, you will see a corresponding arrow-shaped turn signal light flashing on the instrument panel. In some vehicles, the indicator signals will automatically deactivate after a turn has been completed. If this is not the case in your car, be sure to deactivate your indicator light as soon as you are done merging, turning or changing lanes. Leaving the indicator on when you are not planning to turn would confuse the road users around you and could cause a collision.

Gear display

Your vehicle may have gear display lights on the instrument panel. These lights indicate which drive gear the car is currently in. It is more common for gear display lights to be present in automatic vehicles, where the driver has less hands-on interaction with the transmission. If your car has a manual transmission and gear display lights, you can glance at the instrument panel to make sure you have manually chosen the correct gear when shifting up or down.

Warning lights

Any active light on your vehicle’s instrument panel indicates that something requires your attention. It may be an easily rectifiable situation, like if your parking brake is engaged or your high-beam headlights are switched on. Warning lights can also indicate a more serious issue, like an open trunk, poorly inflated tires or a malfunction in the engine.

Quite often, the color of the warning light tells you about the severity of the situation. A yellow or amber warning light may simply indicate that something demands your attention but does not present an immediate hazard, whereas red warning lights are generally linked to dangerous problems. If a red warning light flashes up on your instrument panel, do not drive the vehicle until the situation is resolved.

Do not make the mistake of ignoring any warning light which appears on your dashboard. The vehicle’s built-in computer is designed to detect developing problems in enough time to avert emergency situations and permanent damage to the engine. A problem that could have been fixed cheaply could end up being very expensive if you do not take the car to a mechanic right away.

Check your car owner’s manual for the precise location and meaning of warning lights and indicators that appear on your dashboard. Below, we discuss some of the main warning lights you should keep a lookout for.

Low oil pressure

All modern vehicles have an engine oil pressure sensor and a corresponding warning light on the instrument panel, which will activate should the oil pressure drop below a safe level. If there is insufficient oil in the engine, friction will cause moving parts to wear and eventually grind to a halt, destroying your engine. If the oil pressure warning light comes on, check your oil level with the dipstick and top it up, if the reading indicates it is low. If the oil levels are fine or the oil pressure warning light remains active even after you have added oil, switch off the engine and contact a mechanic.

Check engine light

The “check engine” light is one of the most important warning indicators on the dashboard. Unfortunately, this light could indicate any number of problems with the engine, for example:

• A loose fuel tank cap (this could throw off engine pressure and cause the light to activate)
• A faulty airflow sensor
• Loose or frayed spark plug wires
• A catalytic converter malfunction

In some vehicles, a yellow “check engine” light means there is a minor problem that needs to be investigated, while a red “check engine” light means something has gone seriously wrong and you should stop driving the car immediately. Unless you are a trained mechanic yourself, you will need to get a professional mechanic to investigate the problem if the check engine light remains active.

Engine temperature warning light

If the coolant fluid level becomes too low, or it reaches an unsafe temperature, the engine temperature warning light will activate. If the light comes on while you’re driving, pull over and let the engine cool down before checking the coolant. Keep in mind that low coolant levels could indicate a leak in the engine, which would need to be investigated by a mechanic. You may be able to temporarily fix the problem by topping up the coolant, though this should only serve as a short time solution until you can take the vehicle to be serviced.

In most vehicles, the engine temperature warning light will come on briefly when you start up the engine. This is an automatic bulb test and is no cause for concern, providing the light only remains active for a few seconds.

Antilock braking warning

Most modern vehicles have anti-lock braking systems (ABS). On the instrument panel, an ABS warning light will activate if there is a problem with the anti-lock braking electronics. The ABS warning bulb may briefly illuminate when the engine turns on; as with the engine temperature light, this is nothing to worry about. However, if the ABS warning light remains on, the vehicle’s computer has detected a problem with the system. Even if your ABS seems to be working fine, get the car checked out by a mechanic immediately. Otherwise, your anti-lock brakes may fail you next time you are forced to stop the vehicle suddenly.

Battery alert

The battery is easily the single most important component of your vehicle’s engine. Without the battery, none of the electronic systems will work and the engine will not start. An active battering warning light on the instrument panel could indicate your battery is coming toward the end of its lifespan and needs to be replaced. A persistent battery warning light more commonly indicates a broken or malfunctioning alternator belt. This belt allows the battery to recharge while the engine is running.

If your battery light comes on when you start the vehicle, or while you are driving, take it to a mechanic immediately. A battery that is depleted of charge due to general wear or a broken alternator will not be able to restart the vehicle once the engine is turned off.

Low tire pressure

If the air pressure in any of your car’s tires falls 25% or more below the manufacturer's recommended pressure, the low tire pressure warning bulb on the instrument panel will light-up. This may indicate you have a flat tire, a puncture, or simply that it’s time to top up the air. You can refill your tires yourself at most gas stations, or by taking the car to a mechanic.

Remember that low tire pressure affects the vehicle’s grip on the road’s surface. If the tires are not filled to the manufacturer’s guidelines, the car will not handle as well as usual. When the low tire pressure warning light comes on, pull over and check your tire pressure at the earliest opportunity.

Low fuel

In addition to the fuel gauge, many modern vehicles have a fuel warning light on the instrument panel which will activate if the gas in the fuel tank drops below a certain level. This light will usually come on when you have a few miles of fuel left in the tank – just enough to make it to the nearest gas station. Do not ignore the low fuel warning light. If it comes on, stop what you’re doing and head for a gas station immediately!

Seat belt indicators

When the seat belt symbol on the instrument panel lights up, it means that somebody in the car has not correctly secured their seat belt. We know that seat belts save lives, and this is your warning to buckle up! Most modern vehicles have sophisticated seat belt warning systems that detect how many people are in the vehicle, so the warning light will activate if one of your passengers has not fastened their belt. This is handy if you have children in the backseat who are responsible for securing their own belts.

If the seat belt warning light comes on while you are driving, ask your passengers to check their belts, or pull over to check that any children you are transporting are properly secured. If the seat belt warning light remains active despite all necessary seat belts being fastened, you may need to take the vehicle to a mechanic. This could indicate a problem with a seat belt fastening mechanism – which would be very dangerous in the event of an accident!

Door open

Before starting the vehicle, have a quick glance at the dashboard to make sure the “open door” warning light is not active. This light indicates that one of the vehicle’s doors is not properly latched and could fly open while the car is moving, or during a collision. Check each door by opening and closing it again, until the “open door” light deactivates.

Trunk open

Your instrument panel probably features a “trunk open” warning light, near the seat belt and door warning lights. As you would expect, this illuminated symbol indicates that the trunk is not properly closed. Always get out and check the trunk when this warning light is active, even if it appears to be shut. It could be that the latch has not caught properly, which would mean the trunk is liable to popping open while the car is moving. This may completely obscure your view through the rear window, creating a serious hazard!

High beam indicator

All modern vehicles have a high beam indicator light on the instrument panel, which will light up whenever your high beam lights are active. High beam headlights are powerful and can help you see for greater distances when traveling at night, or in low visibility conditions. Unfortunately, they are powerful enough to dazzle other motorists, cyclists and pedestrians on the roadway ahead of you. Always switch back to low beam lights whenever passing opposing traffic or approaching another road user from behind. The high beam indicator light on the dashboard will help you remember to do this.

Cruise control

You may wish to activate your cruise control when traveling on a long, relatively straight highway and there are few other vehicles on the road. Switching this feature on will set your vehicle at its current speed so that you do not have to keep your foot on the gas pedal. Whenever the cruise control is engaged, a corresponding cruise control indicator light on the dashboard will be active. If the situation on the roadway changes and you need to alter the speed, pressing the cruise control button will deactivate the system and switch off the light.

Getting to know your instrument panel

The instrument panel features discussed in this guide are common among modern vehicles. However, your vehicle may have additional instrument panel lights that are not mentioned here. When familiarizing yourself with the dashboard and instrument panel, it is best to have your vehicle owner’s manual on hand. This book will be able to tell you the meaning and location of every light on the panel. You do not have to memorize all this information right away, though you do need to be able to identify common indicator lights and any warnings which would warrant immediate action.

Never ignore a dashboard warning light!

Many motorists make the mistake of ignoring warning lights on their instrument panel if there is no immediately apparent reason for the light to be active. If the car is running fine despite an active “check engine” light, or if the doors appear to be secured despite an “open door” light, you may be tempted to assume there is no problem besides something being wrong with the warning light itself.

Even if that is the case, a malfunctioning warning light must be fixed! If a warning light is broken, you will not be informed if something does go wrong with its corresponding vehicle feature. Plus, the likelihood is that the warning light is working just fine and the issue it is referring to is not immediately obvious. If any warning light on your dashboard remains active, get the car checked out by a qualified mechanic. It is better to be safe than sorry!