Yamaha YZF-R125 Service Manual: Circuit diagram

Fuel pump system

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Troubleshooting

If the fuel pump fails to operate. NOTE: Before troubleshooting, remove the following part(s): 1. Rider seat 2. Fuel tank ...

Other materials:

Setting the diagnostic mode
1. Set the main switch to "OFF" and the engine stop switch to " ". 2. Disconnect the self-diagnosis signal connector "1", and then connect the FI diagnostic tool "2" as shown. 3. Disconnect the fuel pump coupler. 4. While pressing the "MODE" button, set the main switch to "ON". NOTE: ...

Checking the timing chain tensioner
1. Check: Timing chain tensioner Cracks/damage/rough movement Replace. a. Lightly press the timing chain tensioner rod into the timing chain tensioner housing by hand. NOTE: While pressing the timing chain tensioner rod, wind it clockwise with a thin screwdriver "1" until it stops. b. ...

Air induction system
1. Air induction system hose (air filter case to reed valve assembly) 2. Air induction system reed valve assembly 3. Air induction system hose (reed valve assembly to exhaust pipe) Checking the air induction system Air injection The air induction system burns unburned exhaust gases b ...