YAMAHA YZ250F SELF-DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE

SELF-DIAGNOSTIC FUNCTION TABLE (FOR FUEL INJECTION SYSTEM)

Fault code	Item	Page
12	Crankshaft position sensor: no normal signals are received from the crankshaft position sensor.	Fault code No. 12
13	Intake air pressure sensor: open or short circuit detected.	Fault code No. 13
14	Intake air pressure sensor: hose system malfunction (clogged or detached hose).	Fault code No. 14
15	Throttle position sensor: open or short circuit detected.	Fault code No. 15
16	Throttle position sensor: stuck throttle position sensor is detected.	Fault code No. 16
21	Coolant temperature sensor: open or short circuit detected.	Fault code No. 21
22	Intake air temperature sensor: open or short circuit detected.	Fault code No. 22
30	The vehicle has overturned.	Fault code No. 30
33	Ignition coil: open or short circuit detected in the primary lead of the ignition coil.	Fault code No. 33
39	Injector: open or short circuit detected.	Fault code No. 39
41	ECU: built-in lean angle sensor malfunction.	Fault code No. 41
43	Fuel system voltage: incorrect voltage supplied to the main relay and CCU.	Fault code No. 43
44	EEPROM fault code number: an error is detected while reading or writing on EEPROM.	Fault code No. 44
46	Vehicle system power supply: normal voltage is not supplied to the ECU.	Fault code No. 46
50	ECU: faulty ECU memory.	Fault code No. 50
70	Engine forcibly stops when the vehicle is left idling for a long period of time.	Fault code No. 70

DIAGNOSTIC CODE: SENSOR OPERATION TABLE

Diagnostic code No.	Item	Display	Procedure
01	Throttle angle	Displays the throttle angle.
	Fully closed position	11–14	Check with throttle fully closed.
	Fully opened position	86–92	Check with throttle fully opened.
03	Pressure of suction pipe	Displays the intake air pressure. Check the change of the intake pressure valve when the starter switch is pushed.	The atmospheric pressure is displayed on the Yamaha diagnostic tool.
05	Intake air temperature	Displays the intake air temperature.	Compare the actually measured intake air temperature with the Yamaha diagnostic tool display value.
06	Coolant temperature	Displays the coolant temperature.	Compare the actually measured coolant temperature with the Yamaha diagnostic tool display value.
08	Lean angle sensor	Displays the output voltage.	Remove the ECU, and incline it 45° or more.
	Upright	0.4–1.4 (V)
	Overturn	3.7–4.4 (V)
09	Monitor voltage	Displays the voltage of the external battery connected to the Yamaha diagnostic tool. Approximately 12.0 (V)	—
21	Neutral switch		Operate the shift pedal.
	Gear in neutral	ON
	Gear not in neutral	OFF
25	Gear position switch		Operate the shift pedal.
	Gear in 1st or 2nd	ON
	Gear in other than 1st or 2nd	OFF
60	EEPROM fault code display		—
	No fault	00
	CO adjustment valve	01
	Power Tuner injection correction setting 0–8, or Power Tuner ignition timing correction setting 0–8	07
61	Malfunction history (△) code display *1		—
	There is no history.	00
	There is some history.	Other: Displays the fault code of (△).
62	Malfunction history (△) code erasure *1		Replace all (△) with () by the operation start processing.
	There is no history.	00
	There is some history.	Other: Displays the total number of (×) and (△).
64	Setting history display	Displays the presence or absence of the setting history by Power Tuner.	—
	There is no history.	00
	There is some history.	01
	History is unknown (History data is damaged).	02
65	Setting map erasure	Displays the presence or absence of the setting history by Power Tuner.	Erase all setting maps by the operation start processing.
	There is no setting.	00
	There is some setting.	01
70	Program version number	Displays a program version No.	—

*1: Symbols used in the explanations of the malfunction history

: Normal

×: There is currently a malfunction or abnormal condition.

△: A malfunction or abnormal condition occurred previously, but the affected system or component is currently operating normally.

DIAGNOSTIC CODE: ACTUATOR OPERATION TABLE

Diagnostic code No.	Item	Actuation	Procedure
30	Ignition coil	Actuates the ignition coil five times at one-second intervals. “WARNING” on the Yamaha diagnostic tool blinks five times when the ignition coil is actuated.	Check that a spark is generated five times. Connect an ignition checker.
36	Injector	Actuates the injector five times at one-second intervals. “WARNING” on the Yamaha diagnostic tool blinks five times when the injector is actuated.	TIP: Before performing this operation, be sure to disconnect the fuel pump coupler. Check that injector is actuated five times by listening for the operating sound.

Diagnostic code No.

Item

Actuation

Procedure

Ignition coil

Actuates the ignition coil five times at one-second intervals.

“WARNING” on the Yamaha diagnostic tool blinks five times when the ignition coil is actuated.

Check that a spark is generated five times.