IMMOBILIZER SYSTEM CONSTRUCTION/OPERATION [KEYLESS ENTRY SYSTEM]

• The immobilizer system consists of the key (built-in transponder), coil antenna, instrument cluster, PCM, and the security light (in instrument cluster).

• Keys for use with the immobilizer system have an electronic communication device (transponder) built into the key head that retains specific electronic codes (key ID number).

• The immobilizer system cannot be disabled.

• The engine cannot be started without a previously programmed key.

Caution

• If a metallic or magnetic object is near the key, communication between the key and the vehicle may be obstructed resulting in the inability to start the engine.

• It is also possible that due to other malfunction causes in other systems (such as engine, starter relay) the engine may not start even though the immobilizer system is operating normally. If the immobilizer system is malfunctioning, the security light displays the DTC. The displayed DTC is recorded in the instrument cluster and the PCM.

• The immobilizer system operates automatically when the ignition switch is turned to the LOCK or ACC position. When this occurs, the security light flashes repeatedly approx. 0.1 s every 2 s.

• The order of operation for enabling engine starting is as follows:

• Additional keys can be programmed for starting the vehicle engine.

• When there is one key which can start the engine or an advanced key, the Mazda Modular Diagnostic System (M-MDS) is necessary.

• When there are two keys which can start the engine, the Mazda Modular Diagnostic System (M-MDS) is not necessary. However, if the customer spare key programming is disabled, the Mazda Modular Diagnostic System (M-MDS) becomes necessary.

• When performing the following servicing, it is necessary to reprogram the immobilizer system. Always use the Mazda Modular Diagnostic System (M-MDS) so that the immobilizer system operates normally.

Caution

• If reprogramming is not done using the Mazda Modular Diagnostic System (M-MDS), the engine cannot be started.

Service	Items necessary for procedure (prepare before starting procedure)	Cautionary notes
PCM replacement	• New PCM • Have a key on hand which can start the engine, or an advanced key.	• PCM configuration is necessary.
Instrument cluster replacement	• New instrument cluster • Keys for programming (2 or more)	• Before beginning the procedure, verify that the customer has turned in all of the keys for the vehicle. • Unless the key ID numbers are reprogrammed after the replacement, the engine cannot be started. • The keys (2 or more) prepared before beginning the programming can be new keys or keys which were able to start the engine.
PCM and instrument cluster replaced simultaneously	• New PCM • New instrument cluster • Keys for programming (2 or more)	• Unless keys are reprogrammed after the procedure, the engine cannot be started. Before beginning the procedure, verify that the customer has turned in all of the keys for the vehicle. • The keys (2 or more) prepared before beginning the programming can be new keys or keys which were able to start the engine.