Yamaha YZF-R125 Service Manual: Troubleshooting

Yamaha YZF-R125 Service Manual / Electrical system / Signaling system / Troubleshooting

Any of the following fail to light: turn signal lights, brake light or indicator lights.
The horn fails to sound.
The fuel gauge fails to operate.
The speedometer fails to operate.

NOTE:

Before troubleshooting, remove the following part(s):

1. Seats

2. Fuel tank

3. Left upper side cowling

4. Right side panel

5. Left lower side cowling

Troubleshooting

Circuit diagram

4. Main fuse 5. Main switch 9. Battery 14.Neutral switch 25.ECU (engine control unit) 31.Fuel sender 34.Rear brake light switch 35.Front brake light switch 37.Tail/brake light 38.Rear rig ...

Other materials:

Checking the rectifier/regulator
1. Check: Rectifier/regulator output voltage Out of specification → Replace the rectifier/ regulator. a. Set the engine tachometer to the spark plug lead. b. Connect the pocket tester (DC 20 V) to the rectifier/regulator coupler as shown. Positive tester probe red "1" Negat ...

Introduction
WARNINGDisc brake components rarely require disassembly. Therefore, always follow these preventive measures: Never disassemble brake components unless absolutely necessary. If any connection on the hydraulic brake system is disconnected, the entire brake sy ...

Installing the radiator
1. Fill: Cooling system (with the specified amount of the recommended coolant) Refer to "CHANGING THE COOLANT" on page 3-15. 2. Check: Cooling system Leaks Repair or replace any faulty part. 3. Measure: Radiator cap opening pressure Below the specified pressure Repla ...