Yamaha YZF-R125 Service Manual: Checking the throttle body sensor assembly

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 ...

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 ...

Other materials:

Checking the thermostat
1. Check: Thermostat Does not open at 80.5-83.5 C (176.9-182.3 F)  Replace. a. Suspend the thermostat "1" in a container "2" filled with water. b. Slowly heat the water "3". c. Place a thermometer "4" in the water. d. While stirring the water, observe the thermostat and th ...

Setting the normal mode
NOTE: The engine speed, coolant temperature, and fault code, if detected, can be displayed on the LCD of the FI diagnostic tool when the tool is connected to the vehicle and is set to the normal mode. 1. Set the main switch to "OFF" and the engine stop switch to "". 2. Disconnect the self- ...

Checking the fuel pressure
1. Check: Pressure regulator operation a. Remove the fuel hose connector cover "1" and disconnect the fuel hose "2" from the fuel pump. CAUTION:Although the fuel has been removed from the fuel tank, be careful when removing the fuel hose, since there may be fuel remaining i ...