Q: Car won't start. ETC light comes on. Jeep compass 2013

ETC pertains to the electronic throttle control system. It is possible that a fault exists in the ETC system and so the first thing to do is check for stored diagnostic trouble codes. Be sure you have a fully charged battery that passes an actual load test. Confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. If the immobilizer system is on, you may see a security warning light. If the warning light is on, to temporarily override the immobilizer system, see these instructions. It is not clear from your question if the engine actually cranks, so apart from checking and resolving all trouble codes related to the ETC, or other, systems, if there is no starter motor operation, you will want to check for power AND voltage drops to the starter motor/solenoid. If you want the foregoing diagnostic steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a no start diagnostic and the responding certified mechanic will get this taken care of for you.