What should be done if warning lights appear after repair?

• A. Scan for diagnostic trouble codes
• B. Ignore and continue driving
• C. Reset the trip meter
• D. Replace the battery

Answer: (A)

When warning lights appear after a repair, the first step is to use a diagnostic scan tool to pull diagnostic trouble codes from the vehicle’s control modules. These codes point to the system and specific fault, guiding you to the exact area that needs inspection or recheck. This helps confirm that the repair was successful and that there aren’t any remaining or new issues caused by the repair, including sensor calibrations or module reinitializations that may be required.

After addressing any faults identified by the codes, clear the codes and perform a drive or functional test to verify that the light stays off and the system operates normally.

Ignoring the lights is unsafe because it can mask dangerous problems. Resetting the trip meter does nothing to fix a fault, and replacing the battery won’t address a fault that triggered a warning light.