Yamaha YZF-R125 Service Manual: Checking the radiator fan motor

1. Check:

  • Radiator fan motor Faulty/rough movement → Replace.

a. Disconnect the radiator fan motor coupler from the wire harness.

b. Connect the battery (DC 12 V) as shown.

  • Positive tester probe → blue "1"
  • Negative tester probe → black "2"

Checking the radiator fan motor


c. Measure the radiator fan motor movement.

    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 pro ...

    Checking the coolant temperature sensor
    1. Remove: Coolant temperature sensor WARNING Handle the coolant temperature sensor with special care. Never subject the coolant temperature sensor to strong shocks. If t ...

    Other materials:

    Removing the swingarm
    1. Stand the vehicle on a level surface. WARNINGSecurely support the vehicle so that there is no danger of it falling over. NOTE: Place the vehicle on a suitable stand so that the rear wheel is elevated. 2. Measure: Swingarm side play Swingarm vertical movement a. Me ...

    Incorrect engine idling speed
    Engine 1. Cylinder and cylinder head Incorrect valve clearance Damaged valve train components 2. Air filter Clogged air filter element Fuel system 1. Throttle body Damaged or loose throttle body joint Improperly adjusted engine idling speed (idle adjusting screw) Improper ...

    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  b ...

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