An apparatus is provided for managing communication among a plurality of process means respectively operating on given control programs realizing functions necessary for a vehicle. The plural process means includes a first process means issuing requesting messages for requesting a function and a second process means receiving the requesting message, performing a process requested by each requesting massage, and sending back a response indicating results of the process to the first process means. In the apparatus, storage means stores therein, of the requesting massages issued, only response-waiting messages issued by the first process means and received by the second process means. A measuring component measures an elapse of time from a time when the request stored in the storage is received by the second process means. A determining component determines whether or not the elapse of time measured by the measuring component reaches a preset value.