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Technican looking under the hood of a grey car in a Firestone service shop.

CAR & DIAGNOSTICS TESTING SERVICES

A vehicle diagnostics test helps identify what’s causing performance issues, warning lights, or unusual behavior in your car. Learn how diagnostics work, what’s included, and how we can help pinpoint the problem and recommend the right repair. Schedule your diagnostics service today.

  

DO YOU NEED A VEHICLE DIAGNOSTICS TEST?

Technican looking at a diagnostics tablet near an open car door.

If your vehicle isn’t running as expected or a warning light appears, a diagnostics test can help identify the issue before it leads to more costly repairs. Watch for these common signs that your vehicle may need diagnostics testing:

  • Check engine light is on
  • Decreased fuel efficiency
  • Rough idling or engine misfires
  • Loss of power or poor acceleration
  • Unusual noises or vibrations
  • Trouble starting or stalling
  • Warning lights for other systems (ABS, battery, etc.)

Safety Note: If your check engine light is flashing, your vehicle is stalling, or performance has dropped significantly, more serious issues may be present. Continued driving could cause further damage, so have your vehicle inspected by a Firestone professional as soon as possible.

SCHEDULE AN APPOINTMENT

WHAT HAPPENS DURING A VEHICLE DIAGNOSTICS TEST?

Technican looking under the hood of a grey car in a Firestone service shop.
  • WHAT WE DO: Use advanced diagnostic tools to scan your vehicle’s systems, retrieve error codes, and perform targeted testing to identify the root cause of the issue.
  • WHAT QUALIFIES: Warning lights, performance issues, unusual noises, reduced fuel efficiency, or any concern where the cause isn’t immediately clear.
  • WHAT DOESN’T QUALIFY: The diagnostic trouble code (DTC) is effectively the “tip of the iceberg”. The trouble code takes you to “an area” for further testing to properly determine where the real fault is. The diagnostic fee allows us the time to thoroughly test and accurately determine the real cause of the warning light so we can recommend further service.
  • INCLUDED CHECKS: We may inspect engine performance, sensors, electrical systems, and key components to confirm the issue and rule out related problems.
  • AVERAGE SERVICE TIME: Most diagnostic tests can be completed in about 30–60 minutes, though more complex issues may require additional time for deeper analysis.
  • SERVICE INTERVAL: Diagnostics aren’t scheduled at set intervals. It’s recommended anytime a warning light appears or your vehicle isn’t performing as expected.

VEHICLE DIAGNOSTICS TEST FAQS

Not sure what a diagnostics test can tell you? Here are answers to common questions to help you understand the process and what to expect.

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