Important dashboard information and facts

Gas gauge

Before you start to drive someplace, know roughly how much gas you need to get there and make sure your

gas gauge shows you have enough gas to get to your destination, plus a little more in case you get stuck driving longer than expected before you can fill up again.

The gas gauge should never read much less than a quarter of a tank full before you refill.
(somewhere between the two bottom white lines marked in red in the picture to the right)

Sediment collects in the bottom of your gas tank, driving with very little fuel can cause the sediment to get into the fuelpump and damage it and other parts of the fuel line.


The tachometer measures how fast your crankshaft is spinning the pistons in your engine.

It is basically how hard your engine in working. Generally, the higher the RPMs the more gas you are burning.

The higher the RPMs, the higher your gear needs to be. The average vehicle should see the needle on the tachometer between 2000-3000 RPMs (rotations per minute) while driving under normal conditions.

In the green area on the picture to the right.

Temperature gauge

The temperature gauge is critical to monitor because it doesn't take long to destroy your engine once it overheats.

When moving your eyes every two seconds you should be glancing at your dashboard maybe every 15 seconds.

Watch your temperature gauge as well as your speedometer. The needle should stay just below the halfway mark when the cooling system is working how it's supposed to.

Near where the green line is in the picture.


The speedometer is probably the gauge on your dashboard you'll be watching the most.

Speedometers are not always accurate and can be off as much as 10%.

The size of your tires affect your speedometer reading. Tires too big for your wheels will give your speedometer a lower reading than your actual speed. Tires too small will show a higher speed on your speedometer than your actual speed.

The speedometer in the picture to the right is one of the hardest for some of my students to read because it jumps by 20 mph rather than 10 mph. Just remember the the middle white dots between the numbers
(I enhanced in white) are the next 10 mph.

Click here to see how to test the accuracy of your speedometer

Dashboard lights

Check engine light

This light could look like any of these lights.

It is part of the On board diagnostics System (OBD) and is required by law to keep track of the emissions on any vehicle.

It will come on when a problem is detected with the emissions of your vehicle. It usually doesn't mean you must pull over right away and have it serviced.

If it stays on have your mechanic check it out when you can. There are codes mechanics read that's says what the problem is. Often auto parts stores can read the code for you, though they may not tell you what they mean. sometimes it's a problem with the sensor itself.

Brake light

If your brake light stays on once you start driving, most likely you have left the parking brake on. If you drive too long with your parking brake engaged, it will cause your brakes to get too hot and eventually you will have no braking power. You will have to pull over and let the brakes cool down.

If your brake light comes on while you are driving, it may mean you are a little low on brake fluid. this could happen because of worn brake pads, or a leak in the brake system. You should have it looked at by your mechanic if it is a persistent leak.

Oil light

You don't want to wait to see this light on your dashboard before you find out you don't have oil in your engine.There is most likely significant damage to your engine if this light comes one while you are driving. Pull over right away and put oil in your engine.

Battery light

If the battery warning light comes on this means your battery is not being charged. There is likely something wrong with the alternator or the battery itself. You don't want to drive long with this light on or you will drain the battery and your car will stall right where you are at. Turn off all electrical equipment you don't need to run then pull over to a safe place as soon as you can and fix the problem with your battery.

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