Yamaha YZF-R125 Service Manual: 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 ( × 1) and battery (12 V) to the relay terminal as shown.

Check the relay operation.

Out of specification →  Replace.

Starter relay

Starter relay


1. Positive battery terminal

2. Negative battery terminal

3. Positive tester probe

4. Negative tester probe


Starting circuit cut-off relay

Starting circuit cut-off relay


1. Positive battery terminal

2. Negative battery terminal

3. Positive tester probe

4. Negative tester probe


Headlight relay

Headlight relay


1. Positive battery terminal

2. Negative battery terminal

3. Positive tester probe

4. Negative tester probe


Radiator fan motor relay

Radiator fan motor relay


1. Positive battery terminal

2. Negative battery terminal

3. Positive tester probe

4. Negative tester probe


    Checking and charging the battery
    WARNINGBatteries generate explosive hydrogen gas and contain electrolyte which is made of poisonous and highly caustic sulfuric acid. Therefore, always follow these preventive mea ...

    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 poc ...

    Other materials:

    Checking and lubricating the cables
    The following procedure applies to all of the inner and outer cables. WARNINGDamaged outer cable may cause the cable to corrode and interfere with its movement. Replace damaged outer cable and inner cables as soon as possible. 1. Check: Outer cable Damage Replace. 2 ...

    Periodic maintenance and lubrication chart
    NOTE: The annual checks must be performed every year, except if a kilometer-based maintenance, or for the UK, a mileage-based maintenance, is performed instead. From 30000 km (17500 mi), repeat the maintenance intervals starting from 6000 km (3500 mi). Items marked with an asterisk s ...

    Starting the engine
    In order for the ignition circuit cut-off system to enable starting, one of the following conditions must be met: The transmission is in the neutral position. The transmission is in gear with the clutch lever pulled and the sidestand up. 1. Turn the key to "ON" and make sure ...

    2026 Copyright www.yam-r125.net |