4ways come on and security key light flashes as well as brake light flashes when using turn signals

Be sure to use the correct battery, properly in place, clean the key contacts , See owner's manual for additional information.
There are specialized locksmiths for car keys

No key fob no start,flash signal on then security system on .... no starting...get a key fob for this bike or change the batt fob.

The usual reasons the fob doesn't disarm the security system is:
1) a damaged fob
2) discharged fob battery (Panasonic 2032 or equivalent)
3)electromagnetic interference
a. verify the fob in not in a metal enclosure or within 3" of any other electronic device.
b. place the fob on the seat, start motor and return fob to pocket.
c. move the bike at least 15' from the spot of interference.
With the Fob near the bike, try disabling the security system.

You'll need the PIN number.
If you don't know it, you'll have to change it to a 5 digit PIN number you select.

With the fob present, turn IGN switch:
IGNITION-OFF-IGNITION-OFF-IGNITION
Press LEFT turn signal switch 3 TIMES
Press RIGHT turn signal switch 1 TIME and release
Turn signals will flash 3 times. Current PIN will appear in odometer. The first digit will be flashing.

If changing PIN, enter first digit (a) of new PIN by pressing LEFT signal switch (a) time(s) i.e., for the number 1, press one time. for the number 5, press 5 times.

Press RIGHT signal switch 1 TIME and release.
the new digit (a) will replace the current in odometer window.

Enter second digit (b) with LEFT signal switch.

Repeat until PIN is set.

Once PIN is set (either new or old PIN), to disarm security system, DO NOT sit on seat, lift bike off kick stand, or anything else that will activate the security mode!

Turn IGN to IGNITION.

Quickly (within 2 seconds) hold BOTH turn signal switches until confirmation signal (KEY icon flashes at fast rate, in odometer window, a flashing "-" will be followed by 4 more dashes = "----")

Enter 1st digit (a) in PIN by pressing LEFT turn signal switch (a) times (i.e., 5 times for the number 5)
The 1st "-" will become the 1st digit (i.e., "5")

Press RIGHT switch signal 1 TIME.
The 1st digit is stored and the dash will flash.

Enter 2nd digit (b), and repeat sequence until done.

After the 5th digit is entered, the KEY icon stops blinking, and the system is disarmed.

The system will stay off until the IGN switch is turned off.

If at any time during disarming sequence an error is made, wait 2 minutes before trying again.

If you have a factory security system with the sensors located inside the key fobs you probably need to replace your fob battery.