Yamaha YZF-R125 Service Manual: Intake air pressure sensor

1. Check:

  • Intake air pressure sensor output voltage Out of specification Replace the throttle body.

a. Connect the pocket tester (DC 20 V) to the throttle body sensor assembly coupler as shown.


  • Positive tester probe
    pink/white "1"
  • Negative tester probe
    gray/black "2"

Intake air pressure sensor


b. Set the main switch to "ON".

c. Measure the intake air pressure sensor output voltage.

    Throttle position sensor
    1. Check: Throttle position sensor a. Connect the digital circuit tester to the terminals of the throttle body sensor assembly coupler as shown. Positive tester probe → gray/red t ...

    Intake air temperature sensor
    1. Check: Intake air temperature sensor resistance Out of specification Replace the throttle body. a. Connect the pocket tester ( × 1k) to the throttle body sensor assembly co ...

    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 ...

    Drive chain slack
    The drive chain slack should be checked before each ride and adjusted if necessary. To check the drive chain slack Place the motorcycle on the sidestand. TIP When checking and adjusting the drive chain slack, there should be no weight on the motorcycle. Shift the transmission in ...

    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. b. Connect the pocket tester ( × 1) to the diode terminals as shown. c. Check the diod ...

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