Maintenance Of The Mcu

YCC-S (Yamaha Chip Controlled-Shift) SYSTEM (FJR13AE only)

The transmission gear display on the multi-function meter fails to indicate the selected gear.
   1. Check the gear position sensor.            NG →
      Refer to “CHECKING THE GEAR
      POSITION SENSOR (FJR13AE
      only)” on page 8-235 and “AD-                          Replace the gear position sensor.
      JUSTING THE GEAR POSITION
      SENSOR (FJR13AE only)” on page
      5-11.

            OK ↓
   2. Check the gear position setting.           NG →        Replace the MCU (motor control unit).
      Refer to “Diagnostic code table (Di-
      agnostic code No. Sh_ _65)”.

ET3P66060

MAINTENANCE OF THE MCU

Checking the MCU
1. Check:
 • Terminals “1” of the MCU
   Cracks/damages → Replace the MCU.
 • Terminals “2” of the MCU couplers
   Connection defective, contaminated, come-                                    1
   off → Correct or clean.                                                                           2
NOTE:
If the MCU couplers are clogged with mud or dirt,
clean with compressed air.

ET3P66061

MCU (motor control unit) SELF-DIAGNOSTIC FUNCTION
The MCU (motor control unit) is equipped with a self-diagnostic function in order to ensure that the
YCC-S system is operating normally. If this function detects a malfunction in the YCC-S system, it im-
mediately operates the system under substitute characteristics and lights the YCC-S indicator and
warning light to alert the rider that a malfunction has occurred in the system. Once a malfunction has
been detected, a fault code is stored in the memory of the MCU (motor control unit). After the engine
has been stopped, the lowest fault code number appears on the odometer/tripmeter/fuel reserve trip-
meter LCD. Once a fault code has been displayed, it remains stored in the memory of the MCU (motor
control unit) until it is deleted.
NOTE:
If the engine trouble indicator “1”, YCC-S indicator “2”, and engine trouble warning light “3” all come on,
malfunctions have been detected in both the fuel injection system and the YCC-S system. If this occurs,
the fault codes for the fuel injection system take priority over those for the YCC-S system, so only the
fuel injection system fault codes will appear in the multi-function display. The fault codes for the YCC-
S system will be displayed in the multi-function display after all of the fault codes for the fuel injection
system have been deleted using the reinstatement method.

                                                  8-170