Automotive Diagnostics — Tester Present

Consider tester present service as a way to indicate to the server/ECU that the client/tester is still connected and working. It can be viewed as a heartbeat for servers to recognize if there would be any diagnostic activity

Different sub-functions supported by the tester present are

Important points about tester present

• If the server/ECU is present in a non-default session, the client uses the tester present service to maintain the server in a non-default session.
• To maintain the ECU…