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3 - 23
INSP
ADJ
BATTERY INSPECTION AND CHARGING (TT-R90E)
ÅRelationship between the open-circuit voltage
and the charging time at 20 ˚C (68 ˚F)
(These values vary with the temperature, the
condition of the battery plates, and the electro-
lyte level.)
ıOpen-circuit voltage
ÇCharging time (hours)
ÎTime (minutes)
‰Charging condition of the battery
ÏAmbient temperature 20 ˚C (68 ˚F)
aCharging
bCheck the open-circuit voltage.
Check the charge of the battery, as shown
in the charts and the following example.
Example:
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20 ~ 30% Å
5. Charge:
Battery
(refer to the appropriate charging
method illustration)
WARNING
Do not quick charge a battery.
CAUTION:
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
battery 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
remove it from the machine. (If charging
has to be done with the battery mounted
on the machine, disconnect the negative
battery lead from the battery terminal.)
To reduce the chance of sparks, do not
plug in the battery charger until the bat-
tery charger leads are connected to the
battery.
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3 - 24
INSP
ADJ
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 termi-
nal and that they are not shorted. A cor-
roded battery 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,
disconnect the battery charger and let the
battery cool before reconnecting it. Hot
batteries can explode!
As shown in the following illustration, the
open-circuit voltage of an MF battery sta-
bilizes about 30 minutes after charging
has been completed. Therefore, wait 30
minutes after charging is completed
before measuring the open-circuit volt-
age.
BATTERY INSPECTION AND CHARGING (TT-R90E)
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3 - 25
INSP
ADJ
BATTERY INSPECTION AND CHARGING (TT-R90E)
Charging method using a variable voltage charger
Measure the open-circuit
voltage prior to charging.
Connect a charger and
ammeter to the battery
and start charging.
Is the amperage higher
than the standard charg-
ing amperage written on
the battery?NO
YES Charger
Ammeter
Adjust the voltage to obtain
the standard charging
amperage.
Set the timer to the charging
time determined by the open-
circuit voltage.
Refer to “BATTERY INSPEC-
TION AND CHARGING”.
Adjust the charging voltage to
20 ~ 25 V.
Monitor the amperage for 3 ~
5 minutes. Is the standard
charging amperage
exceeded?
NO YES
If the amperage does not
exceed the standard charg-
ing amperage after 5 min-
utes, replace the battery.
If the required charging time exceeds 5 hours, it is advisable to check
the charging amperage after 5 hours. If there is any change in the
amperage, readjust the voltage to obtain the standard charging
amperage.
Leave the battery unused for more than 30 minutes before measuring
its open-circuit voltage.
12.8 V → Charging is complete.
12.0 ~ 12.7 V → Recharging is required.
Under 12.0 V → Replace the battery.
Leave the battery unused for more
than 30 minutes before measuring its
open-circuit voltage.
Set the charging voltage to 16 ~ 17 V.
(If the charging voltage is lower, charg-
ing will be insufficient, if it is higher, the
battery will be over-charged.)NOTE:
NOTE:
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3 - 26
INSP
ADJ
BATTERY INSPECTION AND CHARGING (TT-R90E)
Charging method using a constant voltage charger
Measure the open-circuit
voltage prior to charging.
Connect a charger and
ammeter to the battery
and start charging.
NO
YESIs the amperage higher
than the standard
charging amperage writ-
ten on the battery?
Charge the battery until the charging
voltage reaches 15 V.
Leave the battery unused for more than
30 minutes before measuring its open-
circuit voltage.
12.8 V → Charging is complete.
12.0 ~ 12.7 V → Recharging is required.
Under 12.0 V → Replace the battery.This type of battery charger cannot
charge an MF battery. A variable
voltage charger is recommended.Leave the battery unused for more
than 30 minutes before measuring its
open-circuit voltage.
Set the charging time to a maximum of 20 hours.
Constant amperage chargers are not
suitable for charging MF batteries.
Charger
Ammeter
Voltmeter
NOTE:
CAUTION:
NOTE:
Page 182 of 364
3 - 27
INSP
ADJ
FUSE INSPECTION (TT-R90E)
6. Install:
Battery
7. Check:
Battery terminals
Dirt → Clean with a wire brush.
Loose connection → Connect properly.
8. Lubricate:
Battery terminal
9. Connect:
Battery lead coupler
(to the battery terminals)
10. Install:
Rear fender
Seat
Recommended lubricant:
Lithium soap base grease
FUSE INSPECTION (TT-R90E)
CAUTION:
To avoid a short circuit, always set the
main switch to “OFF” when checking or
replacing a fuse.
1. Remove:
Seat
Rear fender
2. Check:
Continuity
2Reserve fuse
Checking steps:
Remove the fuse 1.
Connect the pocket tester to the fuse and
check the continuity.
NOTE:
Set the pocket tester selector to “Ω × 1”.
Pocket tester:
YU-03112-C/90890-03112
If the pocket tester indicates “∞”, replace
the fuse.
1 2
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6 - 2
–+ELEC
12
3
456
7
0
98
A
B
F
EC
D
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
TT-R90E
EC611000
ELECTRICAL COMPONENTS
1Main switch
2“ENGINE STOP”
switch
3Thermo switch
4Ignition coil
5CDI unit
6Battery
7Rectifier/regulator
8Neutral switch9CDI magneto
0Carburetor heater
AStarter relay
BFuse
CStart switch
DSpark plug
EStarter motor
FStarting circuit cut-off
relayCOLOR CODE
B ...................... Black
Br .................... Brown
G ..................... Green
O ..................... Orange
R ..................... Red
Sb .................... Sky blue
W ..................... White
Y ...................... Yellow
EC612000
WIRING DIAGRAM
G/WB/RW/LW/RBr G
RW
B/WBr BRB/WBBrR
B/WB/WBB
BR/WBr B
GG/W
B/W
B/W
BrB/RWWOO
B
BW/LY/RR
W
B
B
R
W/RY/R
OFF RUNB
Y/R
Y
Y
OBO BY/RYB B
Sb
W W
Sb
ON OFF
OFFON
Y
BBY/R
Br
Br
B
B
R
RR
R
B
R/WR/W
R/WR/W
R/W
Sb
Sb
RB
R/WB R
Y/RRB W
B/WB
R/W
R/W
R/W
Sb
9
8
1 B5
4
D
2 3
=A
E 6
C
F 7
B/R ................... Black/Red
B/W .................. Black/White
G/W.................. Green/White
R/W .................. Red/White
W/L .................. White/Blue
W/R .................. White/Red
Y/R ................... Yellow/Red
Page 326 of 364
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–+ELEC
ELECTRIC STARTING SYSTEM
(TT-R90E)
STARTING CIRCUIT CUT-OFF SYSTEM
OPERATION
If the main switch is set to “ON”, the starter
motor can only operate if the following condi-
tion is met:
The transmission is in neutral (the neutral
switch is closed).
The starting circuit cut-off relay prevents the
starter motor from operating when this condi-
tion has not been met. In this instance, the
starting circuit cut-off relay is open so current
cannot reach the starter motor. When the
above condition has been met the starting cir-
cuit cut-off relay is closed and the engine can
be started by pressing the start switch.
WHEN THE TRANSMISSION IS
IN NEUTRAL
1Battery
2Main fuse
3Main switch
4Start switch
5Starting circuit cut-off relay
6Neutral switch
7Starter relay
8Starter motor
12
M
3
7
54
6 8
ELECTRIC STARTING SYSTEM (TT-R90E)
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–+ELEC
6 - 8 INSPECTION STEPS
If the starter motor will not operate, use the following inspection steps.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “BATTERY INSPECTION AND CHARGING” section in the CHAPTER 3.
*3 marked: Refer to “MAIN SWITCH INSPECTION” section.
NOTE:
Remove the following parts before inspection.
1) Seat
2) Rear fender
3) Fuel tank
Use 12 V battery in this inspection.
Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112
*1 Check fuseReplace fuse and
check wire harness.
*2 Check battery Recharge or replace.
Check each coupler and
wire connection.Repair or replace.
*3 Check main switch. Replace.
Check starter motor
operation.Repair or replace.
Check starting circuit
cut-off relay.Replace.
Check starter relay. Replace.
Check neutral switch. Replace.
Check start switch. Replace.
OK
OK
OK
OK
OK
OK
OK
OK
No good
No good
No good
No good
No good
No good
No good
No good
No good
ELECTRIC STARTING SYSTEM (TT-R90E)