Yamaha YZF-R125 Service Manual: 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 sensor)
6. FID (fast idle solenoid)
7. Rectifier/regulator
8. Lean angle sensor
9. Starting circuit cut-off relay
10.Turn signal relay
11.Radiator fan motor relay
12.Headlight relay
13.ECU (engine control unit)
14.Fuse box
15.Starter relay
16.Battery
17.Rear brake light switch
18.Sidestand switch
19.Neutral switch
20.Crankshaft position sensor
21.Coolant temperature sensor
22.Speed sensor
23.Radiator fan
24.Horn
- Checking the switches
- Checking the bulbs and bulb sockets
- Checking the fuses
- Checking and charging the battery
- Checking the relays
- Checking the turn signal relay
- Checking the diode
- Checking the spark plug cap
- Checking the ignition coil
- Checking the ignition spark gap
- Checking the crankshaft position sensor
- Checking the lean angle sensor
- Checking the starter motor operation
- Checking the stator coil
- Checking the rectifier/regulator
- Checking the horn
- Checking the fuel sender
- Checking the speed sensor
- Checking the radiator fan motor
- Checking the coolant temperature sensor
- Checking the throttle body sensor assembly
- Checking the fid (fast idle solenoid)
Troubleshooting
If the fuel pump fails to operate.
NOTE:
Before troubleshooting, remove the following part(s):
1. Rider seat
2. Fuel tank
...
Checking the switches
1. Clutch switch
2. Main switch
3. Front brake light switch
4. Sidestand switch
5. Rear brake light switch
6. Neutral switch
7. Turn signal switch
8. Horn switch
9. Dimmer switch
10.Pass ...
Other materials:
Fuel tank cap
Fuel tank cap
Fuel tank cap lock cover
Unlock.
To remove the fuel tank cap
Open the fuel tank cap lock cover.
Insert the key into the lock and turn
it 1/4 turn counterclockwise. The
lock will be released and the fuel
tank cap can be removed.
To install the fuel tank ca ...
Checking the clutch housing
1. Check:
Clutch housing dogs "1"
Damage/pitting/wear
Deburr the clutch
housing dogs or replace the clutch housing.
NOTE:
Pitting on the clutch housing dogs will cause erratic
clutch operation.
2. Check:
Bearing
Damage/wear Replace the
bearing and
clutch housin ...
Protective apparel
The majority of fatalities from motorcycle
accidents are the result of head injuries.
The use of a safety helmet is the
single most critical factor in the prevention
or reduction of head injuries.
Always wear an approved helmet.
Wear a face shield or goggles.
Wind in your unprotecte ...