Yamaha YZF-R125 Service Manual: Troubleshooting
NOTE:
- Before troubleshooting, remove the following part(s):
1. Rider seat
2. Fuel tank
3. Right upper side cowling
4. Passenger seat
Circuit diagram
4. Main fuse
5. Main switch
6. Radiator fan motor fuse
9. Battery
22.Coolant temperature sensor
32.Radiator fan motor relay
33.Radiator fan motor
59.Coolant temperature warning light
64.Ig ...
Other materials:
Checking the front brake hose
1. Check:
Brake hose "1"
Cracks/damage/wear
Replace.
2. Check:
Brake hose holder "2"
Loose connection Tighten the
holder bolt.
3. Hold the vehicle upright and apply the front
brake several times.
4. Check:
Brake hose
Brake fluid leakage Replace the
da ...
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
...
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur during
operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
repre ...