2012 Jeep Wrangler Owner Manual - Page 517

MAINTAINING YOUR VEHICLE 515 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. EMISSIONS INSPECTION AND MAINTENANCE PROGRAMS In some localities, it may be a legal requirement to pass an inspection of your vehicle's emissions control system. Failure to pass could prevent vehicle registration. For states that require an Inspection and Maintenance (I/M), this check verifies the "Malfunction Indicator Light (MIL)" is functioning and is not on when the engine is running, and that the OBD II system is ready for testing. Normally, the OBD II system will be ready. The OBD II system may not be ready if your vehicle was recently serviced, recently had a dead battery or a battery replacement. If the OBD II system should be determined not ready for the I/M test, your vehicle may fail the test. Your vehicle has a simple ignition key-actuated test, which you can use prior to going to the test station. To check if your vehicle's OBD II system is ready, you must do the following: 1. Turn the ignition switch to the ON position, but do not crank or start the engine. 2. If you crank or start the engine, you will have to start this test over. 3. As soon as you turn the ignition switch to the ON position, you will see the MIL symbol come on as part of a normal bulb check. 7