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:

Installing the front wheel (disc)
1. Install: Front brake disc NOTE: Be sure to install the front brake disc with the arrow mark "a" on the disc facing out. Tighten the brake disc bolts in stages and in a crisscross pattern. 2. Check: Front brake disc Refer to "CHECKING THE FRONT BRAKE DISC" on page 4 ...

Overheating
Engine 1. Clogged coolant passages Cylinder head and piston Heavy carbon buildup 2. Engine oil Incorrect oil level Incorrect oil viscosity Inferior oil quality Cooling system 1. Coolant Low coolant level 2. Radiator Damaged or leaking radiator Faulty radiator cap ...

Installing the relay arm
1. Lubricate: Spacers Bearings Oil seals Bolts (unthreaded shaft portion only) 2. Install: Bearing "1" (to the relay arm) Oil seal "2" (to the relay arm) 3. Rear shock absorber assembly 4. Relay arm 5. Connecting arm A. Left side B. Right side ...