ECU YAMAHA WR 450F 2016 Manual PDF

TROUBLESHOOTING
10-1
EAS2GC1406
TROUBLESHOOTING
EAS2GC1407GENERAL INFORMATION
TIP
The following guide for troubleshooting does
not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic
troubleshooting. Refer to the relative procedure
in this manual for checks, adjustments, and re-
placement of parts.
EAS2GC1408STARTING FAILURES
Engine
1. Cylinder and cylinder head• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s) • Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter • Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft • Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank • Empty fuel tank
• Clogged fuel tank breather hose
• Deteriorated or contaminated fuel
• Clogged or damaged fuel hose
2. Fuel pump
• Faulty fuel pump
3. Throttle body • Deteriorated or contaminated fuel
• Sucked-in air Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse • Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
4. Ignition coil • Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
5. Ignition system • Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty ECU
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Improperly grounded circuit
• Loose connections
7. Starting system • Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS2GC1409INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head• Incorrect valve clearance
• Damaged valve train components
2. Air filter • Clogged air filter element
Fuel system
1. Throttle body • Damaged or loose throttle body joint
• Improperly synchronized throttle bodies
• Improper throttle cable free play
• Flooded throttle body

TROUBLESHOOTING
10-2
Electrical system
1. Battery• Discharged battery
• Faulty battery
2. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
3. Ignition coil
• Broken or shorted primary or secondary coil
• Cracked or broken ignition coil
4. Ignition system • Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
EAS2GC1410POOR MEDIUM-AND-HIGH-SPEED PER-
FORMANCE
Refer to “STARTING FAILURES” on page 10-
1.
Engine
1. Air filter
• Clogged air filter element
Fuel system
1. Fuel pump • Faulty fuel pump
2. Throttle body
• Defective throttle body
3. ECU • Faulty ECU
EAS2GC1411SHIFTING IS DIFFICULT
Refer to “CLUTCH” on page 6-41.
EAS2GC1412SHIFT PEDAL DOES NOT MOVE
Engine
1. Shift shaft
• Bent shift shaft
2. Shift drum and shift forks • Foreign object in a shift drum groove
• Seized shift fork
• Bent shift fork guide bar
3. Transmission
• Seized transmission gear
• Foreign object between transmission gears
• Improperly assembled transmission
EAS2GC1413
JUMPS OUT OF GEAR
Engine
1. Shift shaft• Incorrect shift pedal position
• Improperly returned stopper lever
2. Shift forks
• Worn shift fork
3. Shift drum • Incorrect axial play
• Worn shift drum groove
4. Transmission • Worn gear dog
EAS2GC1414CLUTCH SLIPS
Engine
1. Clutch• Improperly assembled clutch
• Loose or fatigued clutch spring
• Worn friction plate
• Worn clutch plate
2. Engine oil
• Incorrect oil level
• Incorrect oil viscosity (low)
• Deteriorated oil
EAS2GC1415CLUTCH DRAGS
Engine
1. Clutch• Unevenly tensioned clutch springs
• Warped pressure plate
• Bent clutch plate
• Swollen friction plate
• Bent clutch push rod
• Damaged clutch boss
• Burnt primary driven gear bushing
2. Engine oil • Incorrect oil level
• Incorrect oil viscosity (high)
• Deteriorated oil
EAS2GC1416OVERHEATING
Engine
1. Cylinder head and piston• Heavy carbon buildup
• Clogged coolant passages
2. Engine oil
• Incorrect oil level
• Incorrect oil viscosity
• Inferior oil quality

TROUBLESHOOTING
10-3
Cooling system
1. Coolant• Low coolant level
2. Radiator • Damaged or leaking radiator
• Faulty radiator cap
• Bent or damaged radiator fin
3. Water pump • Damaged or faulty water pump
• Damaged hose
• Improperly connected hose
• Damaged pipe
• Improperly connected pipe
Fuel system
1. Throttle body • Damaged or loose throttle body joint
2. Air filter • Clogged air filter element
Chassis
1. Brake(s) • Dragging brake
Electrical system
1. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
2. Ignition system • Faulty ECU
• Faulty coolant temperature sensor
EAS2GC1417OVERCOOLING
Cooling system
1. Coolant temperature sensor• Faulty coolant temperature sensor
EAS2GC1418POOR BRAKING PERFORMANCE
Chassis
1. Brake(s)• Worn brake pad
• Worn brake disc
• Air in hydraulic brake system
• Leaking brake fluid
• Defective master cylinder kit
• Faulty brake caliper kit
• Faulty brake caliper seal
• Loose union bolt
• Damaged brake hose
• Oil or grease on the brake disc
• Oil or grease on the brake pad
• Incorrect brake fluid level
EAS2GC1419FRONT FORK OIL LEAKING
Chassis
1. Front fork• Bent, damaged, or rusty inner tube
• Cracked or damaged outer tube
• Improperly installed oil seal
• Damaged oil seal lip
• Incorrect oil level (high)
• Loose damper rod assembly bolt
• Damaged damper rod assembly bolt copper
washer
• Cracked or damaged cap bolt O-ring
EAS2GC1420FAULTY FRONT FORK LEGS
Chassis
1. Front fork • Bent or damaged inner tube
• Bent or damaged outer tube
• Broken fork spring
• Bent or damaged damper rod
• Incorrect oil viscosity
• Incorrect oil level
EAS2GC1421UNSTABLE HANDLING
Chassis
1. Handlebar• Bent or improperly installed handlebar
2. Steering head components • Improperly installed upper bracket
• Improperly installed lower bracket(improperly tightened ring nut)
• Bent steering stem
• Damaged ball bearing or bearing race
3. Front fork leg (s) • Uneven oil levels (both front fork legs)
• Unevenly tensioned fork spring (both front fork legs)
• Broken fork spring
• Bent or damaged inner tube
• Bent or damaged outer tube
4. Swingarm • Worn bearing or bushing
• Bent or damaged swingarm
5. Rear shock absorber assembly (-ies) • Faulty rear shock absorber spring
• Leaking oil or gas
6. Tire (s) • Uneven tire pressures (front and rear)
• Incorrect tire pressure
• Uneven tire wear

LIST OF SELF-DIAGNOSTIC AND FAIL-SAFE ACTIONS
10-5
EAS2GC1425
LIST OF SELF-DIAGNOSTIC AND FAIL-SAFE ACTIONS
LIST OF DIAGNOSTIC CODES
COMMUNICATION ERROR WITH YAMAHA DIAGNOSTIC TOOLFault
code Item Page
12 Crankshaft position sensor: no normal signals are received from the crankshaft position sensor. 9-35
13 Intake air pressure sensor: open or short circuit detected. 9-37
14 Intake air pressure sensor: hose system malfunction (clogged or de- tached hose) 9-38
15 Throttle position sensor: open or short circuit detected. 9-39
16 Throttle position sensor: stuck throttle position sensor is detected. 9-41
21 Coolant temperature sensor: open or short circuit detected. 9-42
22 Intake air temperature sensor: open or short circuit detected. 9-43
30 Latch up detected. 9-44
33 Ignition coil: open or short circuit detected in the primary lead of the ignition coil. 9-45
39 Injector: open or short circuit detected. 9-47
41 Lean angle sensor: open or short circuit detected. 9-48
43 Fuel system voltage: incorrect voltage supplied to the fuel injector and fuel pump. 9-49
44 EEPROM fault code number: an error is detected while reading or writing on EEPROM. 9-50
46 Charging voltage is abnormal. 9-51
50 Faulty ECU memory. (When this malfunction is detected in the ECU, the fault code number might not appear on the meter.) 9-52
Fault code Item Page
Waiting
for con-
nection No communication signal is received from the ECU.
9-52
Er-2 Signals from the ECU cannot be re ceived within the specified period
of time. 9-53
Er-3 Data from the ECU cannot be received correctly. 9-54
Er-4 Registered data cannot be received from the Yamaha diagnostic tool. 9-55

EAS2GC1427
WIRING DIAGRAM
WR450F/WR450FG 2016
1. Joint connector
2. Joint connector
3. Joint connector
4. AC magneto
5. Rectifier/regulator
6. Headlight relay
7. Main relay
8. Engine ground
9. Battery
10. Frame ground
11. Starter relay
12. Main fuse
13. Starter motor
14. Starter relay diode
15. Indicator light
16. Engine trouble warning light
17. Fuel level warning light
18. Resistor
19. Fuel sender
20. Diode
21. Coupler for connecting option-al part
22. ECU (engine control unit)
23. Ignition coil
24. Spark plug
25. Injector
26. Fuel pump
27. Radiator fan motor relay
28. Radiator fan motor fuse
29. Radiator fan motor
30. Joint connector
31. Intake air temperature sensor
32. Coolant temperature sensor
33. Throttle position sensor
34. Intake air pressure sensor
35. Lean angle sensor
36. Engine stop switch
37. Neutral switch
38. Diode
39. Starting circuit cut-off relay
40. Clutch switch
41. Start switch
42. Joint connector
43. Taillight
44. Headlight
45. Coupler for connecting option- al switch
46. Speed sensor
47. Multi-function display
48. Frame ground
49. Ignition coil sub-lead
50. Negative battery lead
51. Engine ground sub-lead
EAS2GC1428
COLOR CODE
BBlack
Br Brown
Ch Chocolate
Dg Dark green
G Green
Gy Gray
LBlue
Lg Light green
O Orange
PPink
RRed
Sb Sky blue
WWhite
Y Yellow
B/L Black/Blue
B/O Black/Orange
B/W Black/White
B/Y Black/Yellow
Br/W Brown/White
G/B Green/Black
G/W Green/White
G/Y Green/Yellow
L/B Blue/Black
L/G Blue/Green
L/R Blue/Red
L/W Blue/White
L/Y Blue/Yellow
P/L Pink/Blue
R/B Red/Black
R/L Red/Blue
R/W Red/White
R/Y Red/Yellow
W/B White/Black
Y/B Yellow/Black
Y/G Yellow/Green
Y/R Yellow/Red