Yamaha Wr250r 2008 Manual

							 
ELECTRICAL COMPONENTS 
8-60 
1. Main switch
2. Battery
3. Main fuse
4. Starter relay
5. ECU
6.  Lean angle sensor
7. Intake solenoid
8.  Throttle position sensor
9. Sidestand switch
10. Neutral switch
11. Rear brake switch
12. Fan motor
13. Rectifier/regulator 
						

							 
ELECTRICAL COMPONENTS 
8-61
23
4
9
5
10
14
13
16
7
11
12
15
8 
						

							 
ELECTRICAL COMPONENTS 
8-62 
1. Horn
2. Fuse box
3. Starter motor
4.  Radiator fan motor relay
5.  Turn signal relay
6. Relay assembly
7. Headlight relay
8.  Intake air temperature sensor
9.  Coolant temperature sensor
10. Speed sensor
11. EXUP servo motor
12. Injector
13. Ignition coil
14. Fuel pump
15. Air cut-off valve 
						

							 
ELECTRICAL COMPONENTS 
8-63 
EAS27980 
CHECKING THE SWITCHES
7
98
1110 4 2
3
5
61 
						

							 
ELECTRICAL COMPONENTS 
8-64 
1. Horn switch
2. Dimmer switch
3.  Turn signal switch
4. Clutch switch
5. Neutral switch
6. Sidestand switch
7. Main switch
8.  Engine stop switch
9. Start switch
10.  Front brake switch
11.  Rear brake switch 
						

							 
ELECTRICAL COMPONENTS 
8-65 
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.
CAUTION:
 
 ECA14370 
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.
NOTE:
 
 
Before checking for continuity, set the pocket tester to “0” and to the “  
Ω  
   
×  
 1” range. 
 
When checking for continuity, switch back and forth between the switch positions a few times.
The terminal connections for switches (e.g., main switch, engine stop switch) are shown in an illustra-
tion similar to the one on below.
The switch positions “a” are shown in the far left column and the switch lead colors “b” are shown in the
top row in the switch illustration.
NOTE:
 
“” indicates a continuity of electricity between switch terminals (i.e., a closed circuit at the re- 
spective switch position). 
The example illustration below shows that: 
There is continuity between red and brown blue/yellow and blue/black when the switch is set to “ON”.  
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
ab 
						

							 
ELECTRICAL COMPONENTS 
8-66 
EAS27990 
CHECKING THE BULBS AND BULB 
SOCKETS 
Check each bulb and bulb socket for damage or
wear, proper connections, and also for continu-
ity between the terminals.
Damage/wear  
→ 
 Repair or replace the bulb,
bulb socket or both.
Improperly connected  
→ 
 Properly connect.
No continuity  
→ 
 Repair or replace the bulb, bulb
socket or both. 
Types of bulbs 
The bulbs used on this vehicle are shown in the
illustration on the left. 
 
Bulbs “a” and “b” are used for the headlights
and usually use a bulb holder that must be de-
tached before removing the bulb. The majority
of these types of bulbs can be removed from
their respective socket by turning them coun-
terclockwise. 
 
Bulbs “c” is used for turn signal and can be re-
moved from the socket by pushing and turning
the bulb counterclockwise. 
Checking the condition of the bulbs 
The following procedure applies to all of the
bulbs.
1. Remove: 
 
Bulb
WARNING
 
EWA13320  
Since the headlight bulb gets extremely hot,
keep flammable products and your hands 
away from the bulb until it has cooled down.
CAUTION:
 
 ECA14380 
 
Be sure to hold the socket firmly when re-
moving the bulb. Never pull the lead, other-
wise it may be pulled out of the terminal in
the coupler. 
 
Avoid touching the glass part of the head-
light bulb to keep it free from oil, otherwise
the transparency of the glass, the life of the
bulb, and the luminous flux will be adverse-
ly affected. If the headlight bulb gets soiled,
thoroughly it with a cloth moistened with 
alcohol or lacquer thinner. 
2. Check: 
 
Bulb (for continuity)
(with the pocket tester)
No continuity  
→  
 Replace.
NOTE:
 
Before checking for continuity, set the pocket 
tester to “0” and to the “  
Ω  
   
×  
 1” range.

 
a. Connect the positive tester probe to terminal
“1” and the negative tester probe to terminal
“2”, and check the continuity.
b. Connect the positive tester probe to terminal
“1” and the negative tester probe to terminal
“3”, and check the continuity.
c. If either of the readings indicate no continuity,
replace the bulb.

 
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C 
						

							 
ELECTRICAL COMPONENTS 
8-67 
Checking the condition of the bulb sockets 
The following procedure applies to all of the bulb
sockets.
1. Check: 
 
Bulb socket (for continuity)
(with the pocket tester)
No continuity  
→ 
 Replace.
NOTE:
 
Check each bulb socket for continuity in the
same manner as described in the bulb section; 
however, note the following.

 
a. Install a good bulb into the bulb socket.
b. Connect the pocket tester probes to the re-
spective leads of the bulb socket.
c. Check the bulb socket for continuity. If any of
the readings indicate no continuity, replace
the bulb socket.

 
EAS28000 
CHECKING THE FUSES 
The following procedure applies to all of the fus-
es.
CAUTION:
 
 ECA13680 
To avoid a short circuit, always set the main
switch to “OFF” when checking or replacing 
a fuse. 
1. Remove: 
 
Side cover (left) 
 
Air scoop (left)
Refer to “GENERAL CHASSIS” on page 4-1.
2. Check: 
 
Main fuse “1” 
 
Fuse box “2”

 
a. Connect the pocket tester to the fuse and
check the continuity.
NOTE:
 
Set the pocket tester selector to “  
Ω  
   
×  
 1”.
b. If the pocket tester indicates “  
∞  
”, replace the
fuse.

 
3. Replace: 
 
Blown fuse

 
a. Set the main switch to “OFF”.
b. Install a new fuse of the correct amperage
rating.
c. Set on the switches to verify if the electrical
circuit is operational.
d. If the fuse immediately blows again, check
the electrical circuit. 
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
1
 
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
2 
						

							 
ELECTRICAL COMPONENTS 
8-68
WARNING
 
EWA13310  
Never use a fuse with an amperage rating
other than that specified. Improvising or us-
ing a fuse with the wrong amperage rating
may cause extensive damage to the electri-
cal system, cause the lighting and ignition
systems to malfunction and could possibly 
cause a fire.

 
4. Install: 
 
Air scoop (left) 
 
Side cover (left)
Refer to “GENERAL CHASSIS” on page 4-1. 
EAS28030 
CHECKING AND CHARGING THE BATTERY
WARNING
 
EWA13290  
Batteries generate explosive hydrogen gas
and contain electrolyte which is made of poi-
sonous and highly caustic sulfuric acid.
Therefore, always follow these preventive
measures: 
 
Wear protective eye gear when handling or
working near batteries. 
 
Charge batteries in a well-ventilated area. 
 
Keep batteries away from fire, sparks or
open flames (e.g., welding equipment,
lighted cigarettes). 
 
DO NOT SMOKE when charging or han-
dling batteries. 
 
KEEP BATTERIES AND ELECTROLYTEOUT OF REACH OF CHILDREN. 
 
Avoid bodily contact with electrolyte as it
can cause severe burns or permanent eye
injury.
FIRST AID IN CASE OF BODILY CONTACT:
EXTERNAL 
 
Skin — Wash with water. 
 
Eyes — Flush with water for 15 minutes and
get immediate medical attention.
INTERNAL 
 
Drink large quantities of water or milk fol-
lowed with milk of magnesia, beaten egg or
vegetable oil. Get immediate medical atten- 
tion.
CAUTION:
 
 ECA13660 
 
This is a sealed battery. Never remove the
sealing caps because the balance between
cells will not be maintained and battery per-
formance will deteriorate. 
 
Charging time, charging amperage and
charging voltage for an MF battery are dif-
ferent from those of conventional batteries.
The MF battery should be charged as ex-
plained in the charging method illustra-
tions. If the battery is overcharged, the
electrolyte level will drop considerably.
Therefore, take special care when charging 
the battery.
NOTE:
 
Since MF batteries are sealed, it is not possible
to check the charge state of the battery by mea-
suring the specific gravity of the electrolyte.
Therefore, the charge of the battery has to be
checked by measuring the voltage at the battery 
terminals.
1. Remove: 
 
Side cover (left)
Refer to “GENERAL CHASSIS” on page 4-1.
2. Disconnect: 
 
Battery band 
 
Battery leads
(from the battery terminals)
CAUTION:
 
 ECA13640 
First, disconnect the negative battery lead 
“1”, and then positive battery lead “2”. 
FusesAmperage 
ratingQ’ty 
Main 30A 1
Headlight 15A 1
Signaling system 10A 1
Ignition 7.5A 1
EFI 7.5A 1
Radiator fan motor 7.5A 1
Backup 7.5A 1
Reserve 30A 1
Reserve 15A 1
Reserve 10A 1
Reserve 7.5A 1 
						

							 
ELECTRICAL COMPONENTS 
8-69 
3. Remove: 
 
Battery
4. Check: 
 
Battery charge

 
a. Connect a pocket tester to the battery termi-
nals.
NOTE:
 
 
The charge state of an MF battery can be
checked by measuring its open-circuit voltage
(i.e., the voltage when the positive battery ter-
minal is disconnected). 
 
No charging is necessary when the open-cir- 
cuit voltage equals or exceeds 12.8 V.
b. Check the charge of the battery, as shown in
the charts and the following example.

 
5. Charge: 
 
Battery
WARNING
 
EWA13300  
Do not quick charge a battery.
CAUTION:
 
 ECA13670 
 
Never remove the MF battery sealing caps. 
 
Do not use a high-rate battery charger
since it forces a high-amperage current
into the battery quickly and can cause bat-
tery overheating and battery plate damage. 
 
If it is impossible to regulate the charging
current on the battery charger, be careful
not to overcharge the battery. 
 
When charging a battery, be sure to re-
move it from the vehicle. (If charging has to
be done with the battery mounted on the
vehicle, disconnect the negative battery
lead from the battery terminal.) 
 
To reduce the chance of sparks, do not
plug in the battery charger until the battery
charger leads are connected to the battery. 
 
Before removing the battery charger lead
clips from the battery terminals, be sure to
turn off the battery charger. 
 
Make sure the battery charger lead clips are
in full contact with the battery terminal and
that they are not shorted. A corroded bat-
tery charger lead clip may generate heat in
the contact area and a weak clip spring may
cause sparks. 
 
If the battery becomes hot to the touch at
any time during the charging process, dis-
connect the battery charger and let the bat- Positive tester probe  
→ 
positive battery terminal
Negative tester probe  
→ 
negative battery terminal 
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20 
– 
30%
A. Open-circuit voltage
B. Charging time
2
1
(V)
(h)
B A
 
A. Open-circuit voltage
B.  Charge of the battery
C. Temperature 20 
°  
C
A
BC