Yamaha FJR13AG Service Manual page 659

Voiding the standard key code:
If a standard key has been lost, it is possible to disable its use by re-registering the remaining standard
key. Standard key registration erases the stored standard key code from the memory, thus disabling
the lost standard key. To re-register, refer to "Standard key registration".
Standard key code voiding method
a. Main switch "ON"
b. Main switch "OFF"
c. LED on
d. LED off
e. Less than 5.0 s
f. Code re-registering key
g. Remaining standard key
h. Registration mode
A. If the immobilizer system indicator light stops
flashing 5 seconds after the first standard key
is registered, the second standard key cannot
be registered.
IMMOBILIZER SYSTEM
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