After refueling, turn the fuel tank cap until you hear a click. Once the cap is released, it will turn slightly in the opposite direction.

Caution
When replacing the fuel tank cap
Do not use anything but a genuine toyota fuel tank cap designed for your vehicle. Doing so may cause a fire or other incident which may result in death or serious injury.
Opening the fuel tank capParts location
System diagram
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Dtc check / clear
Check dtc (using intelligent tester)
Connect the intelligent tester (with can vim) to the
dlc3.
Turn the ignition switch on.
Read the dtcs by following the directions on the
tester screen.
Hint:
Refer to the intelligent tester operator's manual for
further details.
Chec ...
Evaporative emission system reference orifice
Dtc summary
Hint:
The reference orifice is located inside the canister pump module.
Description
The description can be found in the evap (evaporative emission) system (see
page es-335).
Inspection procedure
Refer to the evap system (see page es-340).
Monitor description
5 Hours* af ...