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What is a Diagnostic Tester?

Auto diagnostic testers are tools that help you check issues in your vehicle, so they're repaired properly. When an indicator comes on, such as an ABS or a check engine light, a user can plug these devices into the on-board diagnostic (OBD) connector found under the dash. There are various types of testers that can read specific vehicle makes and models to provide a more accurate diagnosis. Although these tools can clear a dash light, the dash indicator will continue to light up until the root issue is resolved. Certain models help you adjust engine timing, test circuits, check your battery or address other problems under the hood. No matter which model you choose, make sure to follow the instructions to check trouble codes and properly diagnose issues.

Types of Diagnostic Testers

  • OBD II - These are the most common testers available. They work with standard cars, light trucks, minivans, SUVs and hybrids manufactured since 1996. OBD II tools can define what triggered your check engine light, check if your vehicle is ready to pass emission tests and provide data on ABS issues.
  • Timing Lights - These types of tools are solely designed to test the ignition timing and check RPMs.
  • Battery Load Testers - Battery load testers are designed to give you an accurate readout of the strength and condition of your battery.
  • Auto Multimeters/Coil Testers - These testers allow you to check the flow of electricity in your vehicle's electrical circuits.