Ecu Self-Diagnostic Function; Troubleshooting Method - Yamaha CYGNUS RAY ZR 2022 Supplementary Service Manual

EAS30505

ECU SELF-DIAGNOSTIC FUNCTION

The SGCU is equipped with a self-diagnostic function in order to ensure that the fuel injection system
is operating normally. If this function detects a malfunction in the system, it immediately operates the
engine under substitute characteristics and illuminates the engine trouble warning light to alert the rider
that a malfunction has occurred in the system. Once a malfunction has been detected, a fault code
number is stored in the memory of the SGCU
Checking the engine trouble warning light
The engine trouble warning light comes on for around 2 seconds after the main switch has been set to
"ON". If the warning light does not come on the warning light may be defective.
SGCU detects an abnormal signal from a sensor
If the SGCU detects an abnormal signal from a sensor while the vehicle is being driven, the SGCU il-
luminates the engine trouble warning light and provides the engine with alternate operating instructions
that are appropriate for the type of malfunction.
When an abnormal signal is received from a sensor, the SGCU processes the specified values that are
programmed for each sensor in order to provide the engine with alternate operating instructions that
enable the engine to continue operating or stop operating, depending on the conditions.
EAS30506

TROUBLESHOOTING METHOD

The engine operation is not normal and the engine trouble warning light comes on.
1. Check:
• Fault code number
a. Check the fault code number displayed on the computer.
b. Identify the faulty system with the fault code number.
c. Identify the probable cause of the malfunction.
2. Check and repair the probable cause of the malfunction.
Fault code No.
Check and repair. Refer to "TROUBLESHOOTING
DETAILS (FAULT CODE)" on base manual page
7-37.
Monitor the operation of the sensors and actuators in
the diagnostic mode. Refer to "TROUBLESHOOT-
ING DETAILS (FAULT CODE)" on base manual
page 7-37 and "SELF-DIAGNOSTIC FUNCTION
TABLE" on page 5-51.
3. Perform the reinstatement action for the fuel injection system.
Refer to "Confirmation of service completion" in the appropriate table in "TROUBLESHOOTING
DETAILS (FAULT CODE)" on page 7-37.
4. Set the main switch to "OFF", then to "ON" again, and then check that no fault code number is dis-
played.
TIP
If another fault code number is displayed, repeat steps (1) to (4) until no fault code number is displayed.
5. Erase the malfunction history in the diagnostic mode. Refer to "Sensor operation table (Diagnostic
code No. 62)".
TIP
Turning the main switch to "OFF" will not erase the malfunction history.
FUEL INJECTION SYSTEM
Check and repair.
5-47
ELEC
No fault code No.