5 Common Instrument Cluster Gauges Explained

Your instrument cluster is an important part of your dashboard and it contains a wide range of information about your car’s health. It’s important that your instrument cluster is working accurately, otherwise you may not be aware of what’s going on under your hood.

Most commonly found on your instrument cluster are the following gauges:

  • Speedometer
  • Fuel Gauge
  • Tachometer
  • Oil Pressure
  • Temperature Gauge

If you’re not sure exactly what these gauges and dials are telling you, we’ll explain below.



The speedometer is just what it sounds like - it displays the speed you are driving in miles-per-hour (MPH) or kilometers-per-hour (km/h). Usually located in the center of the speedometer dial is a series of numbers called the odometer. This measures the complete number of miles driven by the vehicles over its entire life.

Modern speedometers are usually accurate within 1-2 MPH unless you have made alterations like changing your wheel or tire size. Modifications like these may make recalibration of your speedometer necessary.

Fuel Gauge

fuel gauge

The fuel gauge is another crucial meter that you’ll want to keep an eye on. Unless your vehicle is fully electric, you’ll need gas to make it go. Your fuel gauge is where you turn to get this vital information. Fuel gauges can sometimes read past full when you completely fill the tank - don’t let that worry you. The needle is not broken and will continue to fall into normal ranges as fuel is burned.



Your tachometer provides information that is a bit more technical than the previous two gauges. The tachometer tells you how many rotations per minute (RPM) your engine crankshaft is making. The tachometer usually displays the numbers 1-8 (sometimes 10) and to accurately read the needle, you’ll need to multiply whatever number the needle points to by 1000. For instance, a gauge reading ‘2’ means your engine is at 2000 RPMs.

Oil Pressure

oil pressure gauge

The oil pressure gauge is measuring how well your oil is being circulated through various delivery lines within your engine. The gauge has a range from high (H) to low (L) and any reading that is in the extremes, whether too high or too low, is cause for concern. Your oil pressure needle should settle near the midpoint after your engine has been at idle for 20 minutes or so.

Temperature Gauge

temperature gauge

Lastly, your temperature gauge measures ambient air and fluid temperatures from various sensors around the vehicle. The temperature gauge reads from cold (C) to hot (H) and again, extremes are cause for concern. Your temperature gauge should also stay in the midpoint range while driving.

If you experience trouble with any of the gauges on your instrument cluster, troubleshooting is easy. You can check out this post for a troubleshooting how-to guide. If you’re unable to diagnose the problem on your own, or, if your cluster needs expert repair, ISS Automotive can help. We offer expert instrument cluster repair services and high-quality replacement clusters for Chevy, GM, Buick makes and more. Contact us today and let our experts help you solve your instrument cluster issues.