Check Your Car’s Instruments

How To Check Your Car’s Instruments?

A car’s instruments provide you with information related to the operating system. Therefore, checking your car’s instruments is always helpful. Your car’s instruments consist of a speedometer, fuel gauge, oil pressure, coolant temperature gauge, tachometer, and ammeter or voltmeter. In some cars, there’s also a voltmeter that tells you the condition of your car battery.

Additional instruments are also included in some cars depending on the manufacturer and different options of the car. Things like radios, clocks, or any other similar accessory can’t really be fixed at home. The best you can do is take out their wiring and connections to repair them at the mechanic. Remember, whenever you’re removing the panel or any instrument of your car, always remove the battery and its connections to prevent short circuits or any other risks.

Your car’s instruments are one of the most important parts of your car as they tell you valuable information that always comes in handy. For example, it tells you how fast you’re going, how much fuel is left, and even the condition of your car battery. We’ll let you know how to correctly check your car’s instruments so you can be up to date with your car’s information.

How to remove the instrument panel

At times, you can take out the instrument from the front after you’ve unscrewed the screw heads around the edge. A clip-on plastic trim covers these screws. On several cars, the warning lights and instruments come out at the same time on a panel with a circuit board from the backside.

Earlier cars have separate round instruments kept in place by a U-shaped clamp fitter behind the instrument and presses its front rim against the panel. A clamp holds serrated fasteners connected to two or a singular stud behind the instrument in place. You can undo them with your hand or a thin screwdriver.

Things to be cautious about

  • Avoid getting your hands cut by being extra cautious as tiny sharp and pointed edges aren’t really visible while you’re doing this task.
  • Don’t mess up or strain any wires and avoid damaging printed circuits.
  • Remember to not apply force to anything that doesn’t require force, don’t take stuff apart or together that can’t be joined or taken apart.

Some models of cars have a cowl or a steering wheel shroud that covers the instrument. You’ll have to remove the cowl or dismantle the shroud so the instrument can be removed. You also may have to completely remove the whole dashboard, which can be a complicated and tiring task.

You can use your car’s service manual to easily locate all the screws and the method for performing the task.

Speedometer testing

A speedometer rarely needs testing as it rarely goes wrong. Usually, the mechanically operated drive cable can give you trouble at times. If you hear any noises, they’re usually made by the cable too. However, if you feel like the annoying ticking sound is coming from the instrument and not the cable, you’ll have to replace it with a new unit or repair it. The sound can either be a screeching sound or a ticking sound.

Disconnect the speedometer drive cable from the gearbox end to test it correctly. Turn it with your hand; meanwhile, have someone else watch your speedometer needle. If the speedometer doesn’t register even though the cable turns normal, you’ll have to get a new instrument.

If either the speedometer responds slow or the pointer doesn’t swing fast. The possible cause is that the oil from the cable has entered the mechanism.

Tachometer testing

The tachometers in newer cars are electronically operated. Earlier cars had mechanically driven ones and several worked by a voltmeter. Unfortunately, you can’t repair a tachometer on your own.

If the tachometer shows you wrong, but the engine is running normally. The wiring connecting to the instrument may be the fault. By using a circuit test and a battery, you can see if there are any broken wires. Tighten up any loose connections and clean the rest.

If the fault is still present, remove it and go to an auto electrician who’ll test and repair it.

Ammeter or voltmeter testing

A voltmeter tells you how much the voltage is in the battery, and an ammeter tells you how many amps are of the car battery. These two are very important current measuring indicators, and one of them is connected to the main feed to all the electrics of the car.

If the reading of these instruments is wrong, you’ll have to replace either one of them. If the reading is correct, the circuit is fine.

Battery condition indicator testing

The battery condition indicator is a voltmeter connected to the battery. If the reading it gives is wrong, you’ll have to remove it and link it across the terminal. It should show you the full battery voltage, and if it doesn’t, check the wiring and see if it’s broken or if there’s a fault. If it gives the same reading as before, the whole instrument has a fault. A good quality battery needs a good quality indicator.

Oil, fuel, and temperature gauge faults

All fuel, oil, and temperature gauges in new-age cars work in the same way. The marking in the dial is the only notable difference. Cars back in the day had mechanical oil pressure gauges, and they worked differently. They were connected to the engine with only a thin metal tube. Modern instruments respond to voltage received from a transmitter.

If the instrument readings are either too high or too low, the fault can b in the IVS. If the reading is zero, the reason for the fault may be that the current isn’t reaching them.


Your car has several parts that you have to look after for. These all are important and necessary to avoid hazards, risks, and for your comfort while you’re driving. Checking your car’s instruments every now and then is of utmost importance.