It's common for cars to develop problems and if you want your car to be in perfect working condition you need to diagnose its problems. For easy understanding, car diagnostic tools can be broadly categorized into two main groups: low tech and high tech tools.
Low tech diagnostic tools
These are ideal for older cars that are not computer controlled. Some of the basic tools that fall under this category are: 12v test light, timing light, vacuum gauge, mechanic's stethoscope, vacuum pump, fuel pressure gauge, leak-down detector, and compression tester.
High tech tools
Two main categories of high-tech diagnostic tools are: scan tools and code readers. Code readers are the most basic computer tools that are used in pulling codes from the car's computer. When the code is rolled, you are able to have a starting point for your diagnostic procedure.
In addition to helping you pull the codes, code readers also provide you with basic access to live or freeze frame data from the car's computer.
Scan tools on the other hand are code readers but with added functionalities. Basic scan tools allow you to read and clear codes from the car's computers. The tools also allow you to view all of the available data in the car's computer.
Scan tools have also been shown to have the ability of providing you with more information about the codes.
You should note that the information displayed by the tools depends on the quality of the tool; therefore, if you have a high quality tool, you will see a lot of information; however, if you have a low quality tool you will have access to basic information. You should note scan tools that provide more information are usually more expensive.
While code readers and scan tools are the most important high-tech diagnostic tools, there are others such as multimeters that are great to have. A multimeter is a device that is used in checking problems in the electrical system of the car. For example, you can use it to check wherever the element in your heated O2 sensor is good or not.
This is all you need to know about car diagnostic tools. You should note that the tools are expensive; therefore, you should be very careful when buying them so that you are not ripped off. As rule of thumb you should always do your research in order to identify a reputable store selling high quality tools.