2001 YAMAHA YZ250LC oil

6-1
ELECTRICAL COMPONENTS AND WIRING DIAGRAMELEC
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1CDI unit
2“ENGINE STOP” button
3Ignition coil
4TPS (throttle position sensor)
5Solenoid valve
6CDI magneto
7Spark plug
EC612000
WIRING DIAGRAM
COLOR CODE
B...................Black
L ...................Blue
O ..................Orange
R ..................Red
Y...................Yellow
B/R ...............Brack/Red
B/W ..............Black/White
G/L ..............Green/Blue
G/W ..............Green/White
W/L...............White/Blue
W/R ..............White/Red
6
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6-2
IGNITION SYSTEMELEC
EC620000
IGNITION SYSTEM
EC621002
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
*Clean or replace
spark plug.
Primary coil
Secondary coil
Repair or replace.
Spark
Check entire ignition
system for connection.
Spark gap test
No good
No good
No good
No good
No good
No good No Spark
Check “ENGINE STOP”
button.
Pick-up coil
Source coil
Check ignition coil.
Check CDI magneto.
Replace CDI unit.
Replace.
Replace.
Replace.
Replace.
Replace.
*marked: Only when the ignition checker is used.
NOTE:
9Remove the following parts before inspection.
1) Seat
2) Fuel tank
9Use the following special tools in this inspection.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754Pocket tester:
YU-3112-C/90890-03112
OK
OK
OK
OK
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6-4
IGNITION SYSTEMELEC
EC626002
IGNITION COIL INSPECTION
1. Inspect:
9Primary coil resistance
Out of specification ÕReplace.
2. Inspect:
9Secondary coil resistance
Out of specification ÕReplace.
NOTE:
When inspecting the secondary coil resistance,
remove the spark plug cap.
EC627011
CDI MAGNETO INSPECTION
1. Inspect:
9Pick-up coil resistance
Out of specification ÕReplace.
Tester (+) leadÕOrange lead 1
Tester (–) lead
ÕBlack lead 2
Tester (+) leadÕSpark plug lead 1
Tester (–) lead
ÕOrange lead 2
Primary coil Tester selector
resistance position
0.20~0.30½at
½´ 1
20°C (68°F)
Secondary coil Tester selector
resistance position
9.5~14.3k½at
k½´ 1
20°C (68°F)
Tester (+) leadÕWhite/Red lead 1
Tester (–) lead
ÕWhite/Blue lead 2
Pick–up coil Tester selector
resistance position
248~372½at
½´ 100
20°C (68°F)
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6-5
IGNITION SYSTEMELEC
2. Inspect:
9Source coil 1 resistance
Out of specification ÕReplace.
3. Inspect:
9Source coil 2 resistance
Out of specification ÕReplace.
EC628000
CDI UNIT INSPECTION
Check all electrical components. If no fault is
found, replace the CDI unit. Then check the
electrical components again.
Tester (+) leadÕBlack/Red lead 1
Tester (–) lead
ÕBlacklead 2
Source coil 1 Tester selector
resistance position
720~1,080½at
½´ 100
20°C (68°F)
Tester (+) leadÕGreen/Blue lead 1
Tester (–) lead
ÕGreen/White lead 2
Source coil 2 Tester selector
resistance position
44~66½at
½´ 10
20°C (68°F)
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6-6
SOLENOID VALVE SYSTEMELEC
Check solenoid
valve operation.
Solenoid valve
coil
No good
No good
Check each couplers and
wire connection.
Check solenoid valve.
Repair or replace.
Replace.
Replace.
OK
OK
OKSource coil
No goodReplace.* Check CDI magneto.
Replace CDI unit.
No good
EC650001
SOLENOID VALVE SYSTEM
EC651032
INSPECTION STEPS
If the solenoid valve will not operate, use the following inspection steps.
* marked: Refer to "IGNITION SYSTEM" section.
NOTE:
9Remove the following parts before inspection.
1) Seat
2) Fuel tank
9Use l2V battery in this inspection.
9Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112
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6-7
SOLENOID VALVE SYSTEMELEC
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
9Couplers and leads connection
Rust/ Dust/ Looseness/Short-circuit Õ
Repair or replace.
EC652040
SOLENOID VALVE OPERATION
1. Disconnect the solenoid valve coupler.
2. Connect 12V battery to the solenoid valve
coupler.
3. Inspectt:
9Solenoid valve
1
No click when connecting the battery Õ
Replace.
EC653002
SOLENOID VALVE COIL INSPECTION
1. Inspect:
9Solenoid valve coil resistance
Out of specification ÕReplace.
Tester (+) leadÕRed lead 1
Tester (–) lead
ÕRed lead 2
22.8~27.8½at
20°C (68°F)Solenoid
resistance
Tester selector
position
½´ 10
Battery (+) leadÕRed lead 1
Battery (–) lead
ÕRed lead 2
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6-8
TPS (THROTTLE POSITION SENSOR) SYSTEMELEC
Check entire ignition
system for connection.Repair or replace.
OK
OKTPS coil
No goodReplace.Check TPS.
OKSource coil
No goodReplace.*Check CDI magneto.
TPS input
voltageNo goodReplace.Check CDI unit.
No good
EC690000
TPS (THROTTLE POSITION SENSOR) SYSTEM
EC691001
INSPECTION STEPS
If the TPS will not operate, use the following inspection steps.
*marked: Refer to “IGNITION SYSTEM” section.
NOTE:
9Remove the following parts before inspection.
1) Seat
2) Fuel tank
9Use the following special tools in this inspection.
Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113Pocket tester:
YU-3112-C/90890-03112
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6-9
TPS (THROTTLE POSITION SENSOR) SYSTEMELEC
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
9Couplers and leads connection
Rust/ Dust/ Looseness/Short-circuit Õ
Repair or replace.
EC692000
TPS COIL INSPECTION
1. Remove:
9Carburetor
9Mixing chamber top
Refer to “CARBURETOR AND REED
VALVE” section in the CHAPTER 4.
2. Inspect:
9TPS coil resistance
Out of specification ÕReplace.
3. Inspect:
9TPS coil variable resistance
Check that the resistance in increased as
the lever 1is moved from the full close
position to the full open position.
Out of specification ÕReplace.
Tester (+) leadÕBluelead 1
Tester (–) lead
ÕBlacklead 2
TPS coil Tester selector
resistance position
4~6k½at
k½´1
20°C (68°F)
Tester (+) leadÕYellowlead 2
Tester (–) lead
ÕBlacklead 3
Tester selector
positionTPS coil variable
resistance
Full closed Full opened
Zero~2k½at 4~6k½at
20°C (68°F) 20°C (68°F)
k½´1
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