Yamaha YZF-R125 Service Manual: Troubleshooting

Circuit diagram

4. Main fuse 5. Main switch 9. Battery 17.Engine stop switch 25.ECU (engine control unit) 30.Fuel pump 64.Ignition fuse ...

Electrical components

1. Main switch 2. Clutch switch 3. Front brake light switch 4. Ignition coil 5. Throttle body sensor assembly (intake air pressure sensor, intake air temperature sensor, throttle position se ...

Other materials:

Troubleshooting
The ignition system fails to operate (no spark or intermittent spark). NOTE: Before troubleshooting, remove the following part(s): 1. Seats 2. Fuel tank 3. Right side cover 4. Left side panel 5. Left upper side cowling ...

Checking the thermostat
1. Check: Thermostat Does not open at 80.5-83.5 C (176.9-182.3 F)  Replace. a. Suspend the thermostat "1" in a container "2" filled with water. b. Slowly heat the water "3". c. Place a thermometer "4" in the water. d. While stirring the water, observe the thermostat and th ...

Checking the fuel sender
1. Drain the fuel from the fuel tank. 2. Check: Fuel sender resistance Out of specification → Replace the fuel sender. a. Connect the pocket tester ( × 10) to the fuel sender coupler as shown. Positive tester probe sky blue "1" Negative tester probe orange/white " ...