how to fix a P0442 code on Toyota Highlander XU70 (2020-Present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, smoke machine, basic hand tools, multimeter, replacement gas cap (if necessary).
• Ensure the vehicle is parked on a level surface and the engine is turned off. Disconnect the battery before beginning work.

2. Inspect and Replace the Gas Cap

1. Remove the existing gas cap and inspect it for cracks or a damaged seal.
2. If damaged, replace it with a new gas cap that meets OEM specifications.
3. Reinstall the new gas cap and ensure it is tightened securely.

3. Inspect and Repair EVAP Hoses

1. Locate the EVAP hoses connected to the charcoal canister and purge valve.
2. Check for cracks, loose connections, or signs of wear.
3. If any hoses are damaged, replace them with new hoses that match OEM specifications.
4. Reconnect all hoses securely.

4. Test and Replace Purge Valve (if necessary)

1. Locate the EVAP purge valve and disconnect its electrical connector.
2. Using a multimeter, check for continuity when the valve is energized.
3. If it does not operate correctly, remove the valve and replace it with a new one.
4. Reinstall the new valve and reconnect the electrical connector.

5. Smoke Test the EVAP System

1. Connect the smoke machine to the EVAP test port.
2. Activate the machine to introduce smoke into the system.
3. Look for any visible smoke escaping from cracks or loose fittings.
4. Repair any leaks found using appropriate methods (e.g., replacing hoses or sealing cracks).

6. Clear Codes and Test Drive

1. Reconnect the battery and use the OBD-II scanner to clear the P0442 code.
2. Start the engine and allow it to reach operating temperature.
3. Take the vehicle for a test drive to ensure the check engine light does not reappear.