ELECTRICAL COMPONENTS
8-53
a. Disconnect the diode from the wire har-
ness.
b. Connect the digital circuit tester (
) to the
diode coupler as shown.
c. Check the diode for continuity.
d. Check the diode for no continuity.
EAM30294
CHECKING THE IGNITION SPARK GAP
1. Check:
•
Ignition spark gap
Out of specification
Perform the ignition
system troubleshooting, starting with step (5).
Refer to “TROUBLESHOOTING” on page
8-3.
TIP
If the ignition spark gap is within specification,
the ignition system circuit is operating normally.
a. Remove the spark plug cap from the spark
plug.
b. Connect the ignition checker “1” as
shown.
c. Crank the engine, and measure the igni-
tion spark gap “a”.
d. Crank the engine, and gradually increase
the spark gap until a misfire occurs.
EAM30295
CHECKING THE SPARK PLUG CAP
1. Remove:
•
Spark plug cap
(from the spark plug lead)
2. Check:
•
Spark plug cap resistance
Out of specification
Replace.
a. Connect the digital circuit tester (
) to the
spark plug cap.
No continuity
Tester positive lead
Blue/White “1”
Tester negative lead
Blue/Green, Blue “2”
Continuity
Tester positive lead
Blue/Green, Blue “2”
Tester negative lead
Blue/White “1”
No continuity
Tester positive lead
Brown/White, Brown “3”
Tester negative lead
Blue/Green “4”
Continuity
Tester positive lead
Blue/Green “4”
Tester negative lead
Brown/White, Brown “3”
No continuity
Tester positive prove
Blue/Black “5”
Tester negative prove
Blue/Red “6”
Continuity
Tester positive prove
Blue/Red “6”
Tester negative prove
Blue/Black “5”
A. Diode 1
B. Diode 2
C. Diode 3
L/W
L/G,L
L/B
L/R
Br/W,Br
L/G
1
2
3
5
6
4
Minimum ignition spark gap
6.0 mm (0.24 in)
Ignition checker
90890-06754
Oppama pet–4000 spark checker
YM-34487
2. Spark plug cap
Resistance
7.50–12.50 k
Summary of Contents for YZ450FX 2021
Page 6: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY ...
Page 10: ......
Page 44: ...MOTORCYCLE CARE AND STORAGE 1 32 ...
Page 61: ...TIGHTENING TORQUES 2 16 ...
Page 62: ...CABLE ROUTING DIAGRAM 2 17 EAM20152 CABLE ROUTING DIAGRAM Frame and engine left side view ...
Page 64: ...CABLE ROUTING DIAGRAM 2 19 Frame and engine right side view ...
Page 66: ...CABLE ROUTING DIAGRAM 2 21 Handlebar front view ...
Page 68: ...CABLE ROUTING DIAGRAM 2 23 Frame and engine top view ...
Page 70: ...CABLE ROUTING DIAGRAM 2 25 Frame and battery top view ...
Page 72: ...CABLE ROUTING DIAGRAM 2 27 Rear brake right side view ...
Page 74: ...CABLE ROUTING DIAGRAM 2 29 ...
Page 112: ...ELECTRICAL SYSTEM 3 36 ...
Page 148: ...REAR BRAKE 4 34 system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 25 ...
Page 154: ...HANDLEBAR 4 40 Throttle grip free play 3 0 6 0 mm 0 12 0 24 in ...
Page 189: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 3 1 Connecting rod 2 Oil nozzle 3 Crankshaft ...
Page 191: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 5 5 1 Oil filter element 2 Oil pump 3 Oil strainer ...
Page 270: ...WATER PUMP 6 9 ...
Page 280: ...THROTTLE BODY 7 9 ...
Page 283: ......
Page 284: ...IGNITION SYSTEM 8 1 EAM20142 IGNITION SYSTEM EAM30277 CIRCUIT DIAGRAM ...
Page 288: ...ELECTRIC STARTING SYSTEM 8 5 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM ...
Page 292: ...CHARGING SYSTEM 8 9 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM ...
Page 295: ...CHARGING SYSTEM 8 12 ...
Page 296: ...SIGNALING SYSTEM 8 13 EAM20154 SIGNALING SYSTEM EAM30348 CIRCUIT DIAGRAM ...
Page 300: ...FUEL INJECTION SYSTEM 8 17 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM ...
Page 325: ...FUEL INJECTION SYSTEM 8 42 ...
Page 326: ...FUEL PUMP SYSTEM 8 43 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM ...
Page 358: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15 ...
Page 368: ...CHASSIS 10 9 ...
Page 370: ......
Page 372: ......
Page 373: ...YZ450FXM 2021 WIRING DIAGRAM BEX 2819U 10_W D indd 1 2020 05 29 15 34 30 ...
Page 374: ...YZ450FXM 2021 WIRING DIAGRAM BEX 2819U 10_W D indd 2 2020 05 29 15 34 30 ...