2016 YAMAHA WR 450F relay

FUEL INJECTION SYSTEM
9-49
Fault code No.43
Item Fuel system voltage: incorrect voltage supplied to the fuel in-
jector and fuel pump.
Fail-safe system Able to start engine
Able to drive vehicle
Diagnostic code No. 09
Diagnostic tool display Fuel system voltage
Approximately 12.0 (V)
Procedure Disconnect the main relay, and push the start switch or push down
the kickstarter lever.
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of main relay coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
Between battery terminal and
ECU coupler.
red-red
red-red/white
Between main relay coupler
and ECU coupler.
brown-brown
blue/red-blue/red Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Defective main relay. No operating sound  Re-
place the main relay. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 5.
5 Defective main relay. Execute the diagnostic mode. (Code No. 09)
Fuel system voltage is below
3 V  Replace the main re-
lay. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 6.
6 Malfunction in ECU. Replace the ECU.

FUEL INJECTION SYSTEM
9-50
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. 44
Item EEPROM fault code number: an error is detected while read-
ing or writing on EEPROM.
Fail-safe system Able/Unable to start engine
Able/Unable to drive vehicle
Diagnostic code No. 60
Diagnostic tool display EEPROM fault code display
• 00: No fault
• 01: CO adjustment value
• 07: Setting tool adjustment values 0–8 for fuel injection amount or
ignition timing
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Locate the malfunction Ex ecute the diagnostic mode
(Code No. 60).
00: Go to item 4.
01: Go to item 2.
07: Go to item 3. —
2 “01” is indicated in Diagnostic mode (Code No. 60) EEP-
ROM data error for adjust-
ment of CO concentration Change the CO concentra-
tion, and rewrite in EEPROM.
After this adjustment, push
the engine stop switch, then
push the start switch.
Memory not recovered
 Re-
place the ECU. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Repeat the proce-
dure in item 1. If the same
number is indicated, perform
the procedure in item 4.
3 “07” is indicated in Diagnostic mode (Code No. 60) EEP-
ROM data error for setting
tool adjustment values for
fuel injection amount or igni-
tion timing. Erase the setting map in the
diagnostic mode (diagnostic
code No. 65).
Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Repeat the proce-
dure in item 1. If the same
number is indicated, perform
the procedure in item 4.
4 Malfunction in ECU. Replace the ECU.

FUEL INJECTION SYSTEM
9-52
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. 50
Item
Faulty ECU memory. (When this malfunction is detected in the
ECU, the fault code number might not appear on the meter.)
Fail-safe system Unable to start engine
Unable to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Malfunction in ECU. Replace the ECU. Push the start switch. Check that the fault code
number is not displayed.
Fault code No. waiting for connection
Item No communication signal is received from the ECU.
Fail-safe system Able to start engine (Unable when ECU is malfunctioning)
Able to drive vehicle (Unable when ECU is malfunctioning)
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of Yamaha diag- nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.

FUEL INJECTION SYSTEM
9-55
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. Er-4
Item Registered data cannot be received from the Yamaha diagnos-
tic tool.
Fail-safe system Able to start engine
Able to drive vehicle
Diagnostic code No. —
Diagnostic tool display —
Procedure —
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of Yamaha diag- nostic tool coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
light green–light green Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Yamaha diagnostic tool mal- function. Replace the Yamaha diag-
nostic tool. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 5.
5 Malfunction in ECU. Replace the ECU.

FUEL PUMP SYSTEM
9-57
1. Joint connector
2. Joint connector
9. Battery
10.Frame ground
11.Starter relay
12.Main fuse
22.ECU (engine control unit)
26.Fuel pump
30.Joint connector
36.Engine stop switch
48.Frame ground
50.Negative battery lead

ELECTRICAL COMPONENTS
9-63
1. Intake air temperature sensor
2. Intake air pressure sensor
3. Throttle position sensor
4. Starter relay
5. Main fuse
6. Headlight relay
7. Starting circuit cut-off relay
8. Lean angle sensor
9. Radiator fan motor fuse
10.Radiator fan motor relay
11.Main relay
12.Coolant temperature sensor

ELECTRICAL COMPONENTS
9-72
EAS2GC1387CHECKING THE RELAYS
Check each switch for continuity with the pock-
et tester. If the continuity reading is incorrect,
replace the relay.
1. Disconnect the relay from the wire harness.
2. Connect the pocket tester ( 1) and bat-
tery (12 V) to the relay terminal as shown.
Check the relay operation.
Out of specification  Replace.
Starter relay
Main relay Starting circuit cut-off relay
Headlight relay
Radiator fan motor relay
Pocket tester
90890-03112
Analog pocket tester YU-03112-C
1. Positive battery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive battery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
21
3
4
R/WBr/WR/YL/G
1
2 3
4
L/R BrR
R,R/W
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
1
2 3
4
G/B L/B
L/G,L/W
1
2 3
4
R,R/Y
G R
1
2 3
4
P/L R/L
R/W
Br,R/W

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