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:

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 ...

Removing the cylinder head
1. Align: "I" mark "a" on the generator rotor (with the stationary pointer "b" on the generator cover) a. Turn the crankshaft counterclockwise. b. When the piston is at TDC on the compression stroke, align the "I" mark "c" on the camshaft sprocket with the mark "d" on the cylinder h ...

Replacing the rear brake pads
NOTE: When replacing the brake pads, it is not necessary to disconnect the brake hose or disassemble the brake caliper. 1. Remove: Brake pads Brake pad spring NOTE: To remove the inner brake pad "1", push down on the brake caliper bracket so that there is space to remove the brake pa ...