KEY

PURPOSE:To facilitate control, and to inhibit an increase in cost by a method wherein the code section of a mechanical key is simplified, the mechanical type key is unified with an electronic type key, the keys are inserted into a locking mechanism and an engine is started and operated by the generated code of the electronic type key. CONSTITUTION:Irregularities as a first code are formed at the edge sections of both sides of a key 1 inserting section 2 for a car by combining simple irregularities, and a transmission-circuit housing section 5 is formed to a gripping piece 4. A second code transmitted from the key 1 is complicated at that time, and a switch is closed mechanically by the rotary operation of the key 1 inserted to a locking mechanism body. When the switch is closed, an engine can be started only when the second code transmitted from the key 1 is received simultaneously. Accordingly, the first code is simplified, and the key 1 and the locking mechanism body, into which the key 1 is inserted, can be controlled easily.