IMMOBILIZER SYSTEM CONSTRUCTION/OPERATION [KEYLESS ENTRY SYSTEM]

• When a key is inserted into the key cylinder and turn the ignition switch to ON, the key ID number of the key and the key ID number registered in the instrument cluster are compared. If the comparison is successful, permission is given to start the engine. For PCM control, see Section 01, CONTROL SYSTEM.

• Keys contain a unique ID number that is previously registered in the instrument cluster. Due to this, if immobilizer system component parts are replaced (such as key addition/clearing and instrument cluster replacement), it is necessary to reset the system.

• The immobilizer system can be set so that only the Mazda Modular Diagnostic System (M-MDS) or equivalent must be used to perform system procedures. When using the Mazda Modular Diagnostic System (M-MDS) or equivalent, first security access must be requested. Obtain security access permission according the Mazda Modular Diagnostic System (M-MDS) or equivalent screen and then perform system procedures.

Mazda Modular Diagnostic System (M-MDS) or equivalent setting items	Contents
Programming an additional ignition key	Allows key ID number registration.
Ignition key ID number clearing	Clearing and registration of key ID numbers.
Parameter reset	Initialization of either of the following: • PCM • Instrument cluster
Customer spare key programming enable	“Method for adding other keys using two keys that can start the engine” is enabled. Note • This is the default setting on new vehicles.
Customer spare key programming disable	“Method for adding other keys using two keys that can start the engine” is disabled. Note • When only the Mazda Modular Diagnostic System (M-MDS) or equivalent must be used to register key ID numbers, making a forged key by using two keys that can start the engine is prevented. This function is for use by rental car or other companies with vehicle fleets.

• When immobililizer system component parts (key, Instrument cluster, PCM, and coil antenna) are replaced, the system must be reset as described below. For setting method details, see CX-9 Workshop Manual.

Component part	Setting
Key addition	Key ID number of added key must be registered. Key ID number registration is performed according to the following methods: • Method for registering other keys using two keys that can start the engine • Method using the Mazda Modular Diagnostic System (M-MDS) or equivalent
Key clearing	The registered key ID number can only be cleared using the Mazda Modular Diagnostic System (M-MDS) or equivalent. When clearing a key ID number using the Mazda Modular Diagnostic System (M-MDS) or equivalent, all key ID numbers are cleared.
PCM replacement	• Parameter reset must be performed.
Instrument cluster replacement	• Parameter reset must be performed. • The key ID numbers for all keys that were being used must be registered using the Mazda Modular Diagnostic System (M-MDS) or equivalent. Two or more keys must be registered.
Coil antenna replacement	Resetting of the immobilizer system does not need to be performed.