Troubleshooting Details - Yamaha MT-03 Service Manual

TROUBLESHOOTING DETAILS

This section describes the countermeasures 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 fol-
lowing the order given.
After the check and service of the malfunctioning part has been completed, reset the FI diagnostic
tool display according to the "Reinstatement method".
Fault code No.:
Fault code number displayed on the FI diagnostic tool when the engine failed to work normally.
Refer to "Diagnostic code table".
Diagnostic code No.:
Diagnostic code number to be used when the diagnostic mode is operated. Refer to "DIAGNOS-
TIC MODE".
Fault code No. 12
Used diagnostic code No. – –
Order Item/components
1 Crankshaft position sensor installa-
tion
2 Coupler connections
Crankshaft position sensor cou-
pler
ECU coupler
3 Open or short circuit in the wire har-
ness
4 Defective crankshaft position sen-
sor
Communication error with the FI diagnostic tool
LCD Display
Waiting for connection.... No signals are received from the
ECU.
ERROR 4 Commands from the FI diagnostic
tool are not accepted by the ECU.
Symptom No normal signals are received from the crankshaft position sensor.
Check or maintenance job
Check the sensor for looseness or pinching.
Check the couplers for any pins that may have
pulled out.
Check that the couplers are securely locked.
If necessary, repair the coupler or securely con-
nect it.
Repair or replace if there is an open or short cir-
cuit between the wire harnesses.
Gray - Gray
Green/White - Black/Blue
Replace the sensor if it is defective.
Refer to "IGNITION SYSTEM" on page 8-1.
Symptom
FUEL INJECTION SYSTEM
Probable cause of malfunction
• Improper connection in connecting lead.
• The main switch is OFF position.
• Malfunction in FI diagnostic tool.
• Malfunction in ECU.
• Turn the main switch to "OFF" once, and then set the FI diagnos-
tic tool to CO adjustment mode or diagnostic mode.
• Vehicle battery is insufficiently charged.
• Malfunction in FI diagnostic tool.
• Malfunction in ECU.
7-28
Restore method
Reinstated by crank-
ing the engine.