my Toyota Highlander Third Generation (2014-2019) engine light is on but car runs fine what's wrong

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Ensure the vehicle is parked on a flat surface and the engine is off.
• Disconnect the negative terminal of the battery to prevent electrical shorts.

2. Addressing Error Codes

• Connect the OBD-II scanner to the vehicle’s port.
• Retrieve and document the trouble codes.
• If the codes indicate a minor issue (e.g., P0442 for a small EVAP leak), proceed to inspect the related components.

3. Inspect and Replace Components

• Gas Cap Check
  • Remove the gas cap and inspect the rubber seal for cracks or wear.
  • If damaged, replace the gas cap with a new OEM or quality aftermarket part.
• Emissions System Inspection
  • Inspect the EVAP system hoses for cracks or disconnections.
  • Tighten any loose connections and replace damaged hoses as necessary.

4. Clear Codes and Test

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the engine codes.
• Start the engine and allow it to run for a few minutes to check if the light reappears.