Yamaha YZF-R125 Service Manual: Checking the turn signal relay
1. Check:
Turn signal relay input voltage
Out of specification →The wiring circuit
from
the main switch to the turn signal relay coupler
is faulty and must be repaired.
a. Connect the pocket tester (DC 20 V) to the
turn signal relay terminal as shown.
- Positive tester probe 
brown "1"
- Negative tester probe 
ground 
b. Set the main switch to "ON".
c. Measure the turn signal relay input voltage.
2. Check:
Turn signal relay output voltage
Out of specification Replace.
a. Connect the pocket tester (DC 20 V) to the
turn signal relay terminal as shown. 
Positive tester probe
brown/white "1"
Negative tester probe
ground
b. Set the main switch to "ON".
c. Measure the turn signal relay output voltage.
Checking the relays
Check each switch for continuity with the pocket
tester. If the continuity reading is incorrect, replace
the relay.
1. Disconnect the relay from the wire harness.
2. Connect the pocket tester ( ...
Checking the diode
1. Check:
Diode
Out of specification Replace.
NOTE:
The pocket tester or the analog pocket tester
readings are shown in the following table.
a. Disconnect the diode from the wire harness.
...
Other materials:
Chassis tightening torques
NOTE:
First, tighten the lower ring nut to approximately 48 Nm (4.8 m.kg,
35 ft.lb) with a torque wrench, then
loosen the lower ring nut completely.
Retighten the lower ring nut to 13 Nm (1.3 m.kg, 9.4 ft.lb) with a
torque wrench.
...
Supporting the motorcycle
Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other maintenance
requiring the motorcycle to stand upright.
Check that the motorcycle is in a
stable and level position before starting
any maintenance. A ...
Checking the rear brake disc
1. Remove:
Rear wheel
Refer to "REAR WHEEL" on page 4-12.
2. Check:
Brake disc
Damage/galling → Replace.
3. Measure:
Brake disc deflection
Out of specification → Correct the brake
disc
deflection or replace the brake disc.
Refer to "CHECKING THE FRONT BRAKE
DIS ...