What can be the reason for a long beep eve' time I start my car and eve' 30 minu

Hello, scan the vehicle for trouble codes, The check engine light denotes the presence of OBD-II trouble codes relating to emissions components. There is likely another warning message or light accompanying the beep, but I would also understand if the check engine light is causing the beep - just never heard of it.

Hi,just got your respond. I have checked engine light many times (with Mechanic) but no body really know to tell me exactly what is causing the beep. Also,even when check engine light off,it still beeps.