2001 Edition Yamaha F225A and LF225A Outboards Service Manual, Page 354Get this manual
TRBL SHTG Self-diagnosis
Troubleshooting
Diagnosing the electronic control system
1Connect the special tools to the outboard motor as shownLW
Trouble code indication Example: The illustration code number 23a: Light on, 0.33 second b: Light off, 4.95 seconds b: Light off, 0.33 second d: Light off, 1.65 seconds