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


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    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 ...

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    Circuit diagram
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