If the vehicles diagnostic system determines that the fuel filler cap in loose, improperly installed, or damaged, a “gASCAP” message will be displayed in the instrument cluster. Tighten the gas cap until a “clicking” sound is heard. This is an indication that the gas cap is properly tightened. Press the trip odometer reset button to turn off the message. If the problem persists, the message will appear the next time the vehicle is started. This might indicate a damaged cap. If the problem is detected twice in a row, the system will turn on the MIL. Resolving the problem will turn the MIL off.