Jeep Wrangler: REFUELING THE VEHICLE — GASOLINE ENGINE (IF EQUIPPED) / Loose Fuel Filler Cap Message

After fuel has been added, the vehicle diagnostic system can determine if the fuel filler cap is possibly loose, improperly installed, or damaged. If the system detects a malfunction, the “gASCAP” message will display in the odometer display. Tighten the gas cap until a "clicking" sound is heard. This is an indication that the gas cap is properly tightened. Push the odometer reset button to turn the message off. 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.