Yamaha YZF-R125 Service Manual: 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 FI diagnostic tool.
b. Identify the faulty system with the fault code.
Refer to "Self-Diagnostic Function table".
c. Identify the probable cause of the malfunction.
Refer to "Diagnostic code table".
2. Check and repair the probable cause of the
malfunction.
3. Perform fuel injection system reinstatement action.
Refer to "Reinstatement method" of table in "TROUBLESHOOTING DETAILS" on page 8-41.
4. Set the main switch to "OFF" and back to "ON", and then check that no fault code number is displayed.
NOTE:
If other fault codes are 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)".
NOTE:
Setting the main switch to "OFF" will not erase the malfunction history.
The engine operation is not normal but the engine trouble warning light does not come on.
1. Check the operation of the following sensors
and actuators in the diagnostic mode. Refer
to "Sensor operation table" and "Actuator operation
table".
If a malfunction is detected in the sensors or actuators, repair or replace all faulty parts.
If no malfunction is detected in the sensors and actuators, check and repair the inner parts of the engine.
Self-diagnostic function table
If the ECU detects an abnormal signal from a sensor while the vehicle is
being driven, the ECU illuminates
the engine trouble warning light and provides the engine with alternate
operating instru ...
Diagnostic mode
It is possible to monitor the sensor output data or check the activation of
actuators with the FI diagnostic
tool connected to the vehicle and set to the normal mode or the diagnostic
monitoring ...
Other materials:
General maintenance and lubrication chart
TIP
The air filter needs more frequent service if you are riding in
unusually wet or dusty areas.
Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
Every two years change the brake fluid.
Replace the brake hoses every four ye ...
Air induction system
1. Air induction system hose (air filter case to
reed valve assembly)
2. Air induction system reed valve assembly
3. Air induction system hose (reed valve
assembly to exhaust pipe)
Checking the air induction system
Air injection
The air induction system burns unburned exhaust
gases b ...
Checking the horn
1. Check:
Horn resistance
Out of specification Replace.
a. Disconnect the horn connectors from the
horn terminals.
b. Connect the pocket tester ( × 1) to the horn
terminals.
Positive tester probe
horn terminal "1"
Negative tester probe
horn terminal "2"
c. Measure t ...