Yamaha YZF-R125 Service Manual: Fuel pump system

Troubleshooting details

This section describes the measures per fault code number displayed on the FI diagnostic tool. Check and service the items or components that are the probable cause of the malfunction following t ...

Circuit diagram

4. Main fuse 5. Main switch 9. Battery 17.Engine stop switch 25.ECU (engine control unit) 30.Fuel pump 64.Ignition fuse ...

Other materials:

Checking the ignition spark gap
1. Check: Ignition spark gap Out of specification Perform the ignition system troubleshooting, starting with step 5. Refer to "TROUBLESHOOTING" on page 8-3. NOTE: If the ignition spark gap is within specification, the ignition system circuit is operating normally. a. Disconnect the spa ...

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 probe gray "1" Negative tester probe gray/black "2" b. Set the main switch to "ON". c. ...

Removing the piston
1. Remove: Piston pin clips "1" Piston pin "2" Piston "3" CAUTION:Do not use a hammer to drive the piston pin out. NOTE: Before removing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip from falling in ...