What might cause my 2015 Jeep Patriot check engine light to come on?

A check engine light in the 2015 Jeep Patriot may be illuminated due to a vacuum or emissions leak which can be as simple as a loose gas cap. More serious reasons include a faulty O2 sensor or a failing catalytic converter. An O2 sensor often needs to be replaced when a sudden drop in fuel economy is noticed. The sensor is responsible for monitoring the amount of unburned oxygen still in the exhaust. This data is used to determine the engine's air/fuELRatio. The cat helps transform carbon monoxide into carbon dioxide and can become clogged and d***y over time. When the ECU senses imbalanced emission readings, the "check engine" light will be illuminated. If any one of these readings become interrupted the "check engine" light in a Jeep Patriot will be triggered.