Check engine light without any false code Or any effect on driving

Why is the check engine code hidden and not showing? If you disconnect the battery from the car, then reconnect it and connect the contact, it will appear once and less clearly than the other symbols. 

Good morning, i have problem withe EPC every time i turn the car on and after 1 to 5 min the check lamp of epc is on, i have already checked the (papion, injecter, sond, bougie

Check light blinking again and again

Engine check light continuously blinking

Eloop problem and have blinking lights isystem