Yamaha YZF-R125 Service Manual: Troubleshooting
Any of the following fail to light: headlight, high beam indicator light, taillight, license plate light, auxiliary light or meter light.
NOTE:
- Before troubleshooting, remove the following part(s):
1. Seats
2. Fuel tank
Circuit diagram
4. Main fuse
5. Main switch
9. Battery
25.ECU (engine control unit)
36.License plate light
37.Tail/brake light
44.Headlight relay
46.Pass switch
47.Dimmer switch
51.Headlight (low beam)
...
Signaling system
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Other materials:
Disassembling the water pump
1. Remove:
Water pump seal "1"
NOTE:
Remove the water pump seal from the inside of
the water pump housing "2".
2. Remove:
Bearing "1"
NOTE:
Remove the bearing from the outside of the water
pump housing "2".
...
Checking the speed sensor
1. Check:
Speed sensor output voltage
Out of specification → Replace.
a. Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness end) as
shown.
Positive tester probe
gray "1"
Negative tester probe
gray/black "2"
b. Set the main switch to "ON".
c. ...
Installing the front brake master cylinder
1. Install:
Brake master cylinder "1"
Brake master cylinder holder "2"
NOTE:
Install the brake master cylinder holder with the
arrow mark "a" pointing forward.
Align the end of the brake master cylinder holder
with the punch mark "b" on the handlebar.
First, tighten the front bo ...