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FUEL INJECTION SYSTEM
8-14
Fault code
12
Symptom
Crankshaft position sensor: no normal signals are received
from the crankshaft position sensor.
Fail-safe system
Unable to start engine
Unable to drive vehicle
Diagnostic code No.
—
Diagnostic tool display
—
Procedure
—
Or-
der
Probable cause of malfunc-
tion and check
Maintenance job
Reinstatement method
1
Connection of crankshaft po-
sition sensor coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).
Improperly connected
Connect the coupler secure-
ly, or repair/replace the wire
harness.
Crank the engine.
Fault code No. is not dis-
played
Repair is finished.
Fault code No. is displayed
Go to next order.
2
Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler, and
check the pins (for bent or
broken terminals and locking
condition of the pins).
Improperly connected
Connect the coupler secure-
ly, or repair/replace the wire
harness.
Crank the engine.
Fault code No. is not dis-
played
Repair is finished.
Fault code No. is displayed
Go to next order.
3
Wire harness continuity.
Open or short circuit
Re-
place the wire harness.
Between the crankshaft posi-
tion sensor coupler and ECU
coupler.
gray–gray
black/blue–black/blue
Crank the engine.
Fault code No. is not dis-
played
Repair is finished.
Fault code No. is displayed
Go to next order.
4
Mounted condition of crank-
shaft position sensor.
Check for looseness or
pinching.
Check the gap between the
crankshaft position sensor
and the pickup rotor.
Improperly mounted sensor
Remount or replace the
Crank the engine.
Fault code No. is not dis-
played
Repair is finished.
Fault code No. is displayed
Go to next order.
5
Defective crankshaft position
sensor.
Check the crankshaft position
sensor.
Crank the engine.
Fault code No. is not dis-
played
Repair is finished.
Fault code No. is displayed
Go to next order.
6
Faulty ECU
Replace the ECU.
Summary of Contents for YZ250F 2014
Page 4: ......
Page 10: ......
Page 12: ......
Page 16: ...LOCATION OF IMPORTANT LABELS 1 2 EUR ...
Page 17: ...LOCATION OF IMPORTANT LABELS 1 3 AUS NZL ZAF ...
Page 42: ...CLEANING AND STORAGE 1 28 ...
Page 68: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 25 ...
Page 70: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 27 ...
Page 72: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 29 ...
Page 74: ...CABLE ROUTING DIAGRAM 2 31 EAS1SM1064 CABLE ROUTING DIAGRAM ...
Page 76: ...CABLE ROUTING DIAGRAM 2 33 ...
Page 78: ...CABLE ROUTING DIAGRAM 2 35 ...
Page 80: ...CABLE ROUTING DIAGRAM 2 37 ...
Page 82: ...CABLE ROUTING DIAGRAM 2 39 ...
Page 84: ...CABLE ROUTING DIAGRAM 2 41 ...
Page 190: ...CHAIN DRIVE 4 66 ...
Page 250: ...OIL PUMP AND BALANCER GEAR 5 57 c d 6 6 7 8 8 b ...
Page 286: ......
Page 295: ...CHARGING SYSTEM 8 9 EAS1SM1326 ...
Page 321: ...FUEL PUMP SYSTEM 8 35 EAS1SM1333 ...
Page 322: ...ELECTRICAL COMPONENTS 8 36 ELECTRICAL COMPONENTS EAS1SM1334 9 10 1 2 3 4 5 6 7 8 ...
Page 324: ...ELECTRICAL COMPONENTS 8 38 CHECKING THE SWITCHES B Y P Sb 2 1 ...
Page 325: ...ELECTRICAL COMPONENTS 8 39 1 Engine stop switch 2 Neutral switch ...
Page 334: ...ELECTRICAL COMPONENTS 8 48 ...
Page 342: ...LIST OF SELF DIAGNOSTIC AND FAIL SAFE ACTIONS 9 7 ...
Page 353: ......
Page 354: ...PRINTED IN JAPAN E PRINTED ON RECYCLED PAPER ...