diagram YAMAHA YZ250F 2014 Owner's Guide

CHARGING SYSTEM
8-8
TROUBLE SHOOTING
The condenser is not being charged.
TIP
Before troubleshooting, remove the following part (s):
1. Seat
2. Air scoop (left)
1. Check the entire charging system’s
wiring.NG 
Reconnect.
OK 
2. Check the rectifier/regulator.
Refer to “CHECKING THE RECTI-
FIER/REGULATOR” on page 8-43.NG 
Replace the rectifier/regulator.
OK 
3. Check the stator coil.
Refer to “CHECKING THE STA-
TOR COIL” on page 8-43.NG 
Replace the stator coil.
OK 
4. Check the charging system wire
harness.
Refer to “CIRCUIT DIAGRAM” on
page 8-6.NG 
Repair or replace the wire harness.
OK 
Replace the condenser.

FUEL INJECTION SYSTEM
8-10
FUEL INJECTION SYSTEM
EAS1SM1327CIRCUIT DIAGRAM
B/LGy
BR
A
A
AA
B
RR R R R R R
B
B
B
RR
R
Lg
LgB/WB/Y
B/YB
B
BP
PP
Sb
B/LP/B
P/B
YL
YL
L
G/WBr/W
G/WBr/W
B/LB/L
B/L
B/L
B/R
B/R
R/B
R/B
O
OROR
OR
R
R
SbB
GyR
B/W
P L B/L
B/L Gy B/L B/L B/L B/L B/L
LL
PP
BBBB
PP
Sb
RB
B/RR
RB
B/Y PSb
BB
RR/B
LYB/L
B/W RLg
B/LBr/W
B/L P/B LB/LG/W
BB/Y
BB/L B/L B/L B/L B/L B/LBBBBRR
PPPL L LRR RR R
B
O P
Gy
R
B/Y Sb
P/B
R/B Lg B/RG/WBr/WB/L L Y
RB
B/L
Gy
R
O
O
R(BLACK) (BLACK)
B/W
4
1
3
2
5
67
8
10
9
1211
13
1415
16
17

FUEL PUMP SYSTEM
8-32
EAS1SM1330
FUEL PUMP SYSTEM
EAS1SM1331CIRCUIT DIAGRAM
B/LGy
BR
A
A
AA
B
RR R R R R R
B
B
B
RR
R
Lg
LgB/WB/Y
B/YB
B
BP
PP
Sb
B/LP/B
P/B
YL
YL
L
G/WBr/W
G/WBr/W
B/LB/L
B/L
B/L
B/R
B/R
R/B
R/B
O
OROR
OR
R
R
SbB
GyR
B/W
P L B/L
B/L Gy B/L B/L B/L B/L B/L
LL
PP
BBBB
PP
Sb
RB
B/RR
RB
B/Y PSb
BB
RR/B
LYB/L
B/W RLg
B/LBr/W
B/L P/B LB/LG/W
BB/Y
BB/L B/L B/L B/L B/L B/LBBBBRR
PPPL L LRR RR R
B
O P
Gy
R
B/Y Sb
P/B
R/B Lg B/RG/WBr/WB/L L Y
RB
B/L
Gy
R
O
O
R(BLACK) (BLACK)
B/W
4
1
3
2
5
67
8
10
9
1211
13
1415
16
17

FUEL PUMP SYSTEM
8-34
TROUBLESHOOTING
The fuel pump fails to operate.
TIP
Before troubleshooting, remove the following part(s):
1. Seat
2. Side cover (left/right)
3. Air scoop (left/right)
4. Fuel tank
5. Air filter case cover
1. Check the fuel pump system wire
harness connections.NG 
Reconnect.
OK 
2. Check the engine stop switch.
Refer to “CHECKING THE
SWITCHES” on page 8-38.NG 
Replace the engine stop switch.
OK 
3. Check fuel pressure.
Refer to “CHECKING THE FUEL
PRESSURE” on page 7-3.NG 
Replace the fuel pump.
OK 
4. Check the fuel pump system wire
harness.
Refer to “CIRCUIT DIAGRAM” on
page 8-32.NG 
Repair or replace the wire harness.
OK 
Replace the ECU.

ELECTRICAL COMPONENTS
8-40
Check each switch for continuity with the pocket tester. If the continuity reading is incorrect, check
the wiring connections and if necessary, replace the switch.
ECA14370
NOTICE
Never insert the tester probes into the coupler terminal slots “1”. Always insert the probes
from the opposite end of the coupler, taking care not to loosen or damage the leads.
TIP
• Before checking for continuity, set the pocket tester range to “ 1” to make a “0” adjustment.
• When checking for continuity, switch back and forth between the switch positions a few times.
Terminal connections of the switch are shown in the terminal connection diagram below.
The switch positions “a” are shown in the far left column and the switch lead colors are shown in the
top row in the switch illustration.
TIP
“ ” indicates continuity between switch terminals (i.e., a closed circuit at each switch posi-
tion).
The example illustration below shows that:
There is continuity between red and brown when the switch is “ON”.Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
a

EAS1SM1381
WIRING DIAGRAM
YZ250F 2014
1. Crankshaft position sensor
2. AC magneto
3. Rectifier/regulator
4. Joint connector
5. Condenser
6. Coupler for connecting option-
al part
7. Engine stop switch
8. Neutral switch
9. ECU
10. Ignition coil
11. Spark plug
12. Injector
13. Fuel pump
14. Intake air temperature sensor
15. Coolant temperature sensor
16. Throttle position sensor
17. Intake air pressure sensor
EAS1SM1382COLOR CODE
BBlack
Gy Gray
LBlue
Lg Light green
O Orange
PPink
RRed
Sb Sky blue
Y Yellow
B/L Black/Blue
B/R Black/Red
B/W Black/White
B/Y Black/Yellow
Br/W Brown/White
G/W Green/White
P/B Pink/Black
R/B Red/Black

A
A
A
A
B
R R R R R R RB
B
B
R
RRLgLg
B/W
B/YB/Y
B
B
B
PPPSb
B/L
P/B
P/B
Y
L
Y
L
L
G/W
Br/W
G/W
Br/WB/L
B/L
B/L
B/L
B/RB/R
R/BR/B
O
O
R
O
R
O
R
R
R
Sb
B
Gy
R
B/W
P
LB/L
B/L Gy B/L B/L B/L B/L B/L
L L
P P
B B B B
4
1
32
5
\f
7
8
10
\b
12
11
13
14
15
1\f
17
P P
Sb
R B
B/RR
RB
B/LGyBR
B/Y PSb
B B
RR/B
L YB/L
B/W RLg
B/LBr/W
B/L P/B L
B/LG/W
BB/Y
B
B/L B/L B/L B/L B/L B/LB B B B R R
P P P L L LR R R R R
B
O P
Gy
R
B/Y SbP/B
R/B Lg B/RG/WBr/WB/L L Y
R BB/L
Gy
ROOR(BLACK) (BLACK)
B/W
WIRING DIAGRAM
YZ250F (E) 2014 SCHÉMA DE CÂBLAGE
YZ250F (E) 2014
SCHALTPLAN
YZ250F (E) 2014SCHEMA ELETTRICO
YZ250F (E) 2014
1SM-28199-30_W.D.indd 12013/09/03 11:24:21

A
A
A
A
B
(BLACK) (BLACK)
4
1
32
5
6
7
8
10
9
12
11
13
14
15
16
17
WIRING DIAGRAM
YZ250F (E) 2014 SCHÉMA DE CÂBLAGE
YZ250F (E) 2014
SCHALTPLAN
YZ250F (E) 2014SCHEMA ELETTRICO
YZ250F (E) 2014
1SM-28199-30_W.D.indd 22013/09/03 11:24:21