Looks like maybe a check engine light. Not really sure. Somebody should clear this up for you. BTW what year and make and model is your truck. Just trying to ask the important questions first to get your answer a little faster.
Be patient. The replies will come from our resident Hino mechanics greasytshirt and Hino123. They have a wealth of information. If you can’t wait feelfree to send them a PM and ask away.