Complete Guide to Car Gauges

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Complete Guide to Car Gauges

The dashboard of a car has several indicator gauges, which allow the driver to monitor a variety of functions and how well the car is operating. Several gauges are standard on nearly all cars on the road today, but depending on the make, model, and age of the car, it may have an indicator light instead of a gauge. Aftermarket gauges allow drivers to replace warning lights on most vehicles.


Standard dashboard gauges

All modern, and many older, cars have three standard dashboard gauges: the speedometer, temperature, and fuel gauges. These gauges are usually located in front of the driver.


The speedometer measures the speed that the car is travelling. It is very accurate unless the driver has changed the tyre size. A larger tyre makes the speedometer read a slower speed than the car is actually travelling. In addition, if the transmission needs replacement, the technician should adjust the speedometer gear so it provides an accurate speed after installation of the new transmission.


The temperature gauge measures the engine coolant's temperature. When the car warms up, the gauge reads in the normal range. If the gauge shows that the engine is cold after driving for a few miles or shoots up into the hot range, the driver should take the car to a mechanic. He or she should not drive a car that is overheating; it can severely damage the engine.


The fuel gauge measures the amount of petrol or diesel left in the tank. An indicator light lets the driver know that the fuel is low. In addition to a dashboard gauge, some new cars also have a digital display that shows the car's fuel economy, displaying the kilometres per litre as the car accelerates and decelerates.


More gauges

In addition to the three primary gauges, many cars have several other gauges on the dashboard. If the car does not have a gauge, it generally has a warning light.


The tachometer indicates the engine's revolutions per minute. When driving a manual transmission, the tachometer helps the driver determine the best time to shift gears. If the tachometer shows higher RPMs than normal when at speed or accelerating, or shoots into the red zone, the driver should take the car to a mechanic.

Oil pressure gauge

The oil pressure gauge does not indicate the amount of oil in the engine, but instead measures the oil pressure in kilopascals (kPa). If the gauge drops to a low level or an oil pressure light comes on, the driver should pull to the side of the road in a safe location. After the car cools down, the driver can check the oil and add more if necessary.

Charging system

A car may have a gauge to indicate problems with the charging system. The voltmeter measures the volts passing through the system. Between 14 and 15 volts is a normal range. If the gauge consistently shows a lower or higher amount, the driver should have the belts, alternator, and voltage regulator checked.


Additional indicators

Cars have a number of other warning lights that the driver should stay aware of while starting the engine and driving. The check engine, airbag, and oil lights turn off after the engine starts. A seatbelt indicator tells the driver that one or more passengers have not fastened their seatbelts, while a door indicator shows that a door is still open.

Check engine

If the check engine light stays on, it may be as minor as a loose fuel cap or indicate serious engine problems. The driver should first check the fuel cap to ensure that it is tightly closed. If the fuel cap is the problem, the light usually goes off within a few miles. If the light does not go off, a mechanic can diagnose the problem by connecting the car to diagnostic equipment.

Low tyre pressure

Some cars have a tyre pressure monitoring system, which indicates that there is a tyre with dangerously low air pressure. The warning light is not meant to replace normal tyre maintenance, including checking the tyre pressure manually with a tyre gauge at least once per month.


How to buy car gauges on eBay

When searching for replacement or aftermarket gauges among the vast array of listings on eBay, use the search bar found on every page to refine your search. Add keywords, such as "speedometer" and the car's make, model, and year, and then click on the search button to view descriptions and photographs of gauges that fit your car. You can also use the available filters to narrow down your options. Once you have selected the correct part, you are sure to be back on the road again in no time.

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