PERIODIC MAINTENANCE AND MINOR REPAIR
6-39
2
3
4
5
67
8
9
5. Remove the auxiliary light bulb
socket (together with the bulb) by
turning it counterclockwise.
6. Remove the defective bulb by pull-
ing it out.7. Insert a new bulb into the socket.
8. Install the socket (together with the
bulb) by turning it clockwise.
9. Place the turn signal light unit in
the original position, and then in-
stall the screws.
10. Install the windshield by installing
the screws.
11. Install panel A.
EAU25880
Troubleshooting
Although Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur dur-
ing operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your scooter re-
quire any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the scooter prop-
erly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look like
Yamaha parts, but they are often inferi-
or, have a shorter service life and can
lead to expensive repair bills.
1. Screw
2. Front turn signal light unit
1. Auxiliary light bulb socket
1
2
1
PERIODIC MAINTENANCE AND MINOR REPAIR
6-40
1
2
3
4
5
6
7
8
9
EAU42700
Troubleshooting charts
Starting problems or poor engine
performance
WARNING
EWA10840
Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Operate the electric starter.
SPECIFICATIONS
8-2
2
3
4
5
6
7
89
Secondary reduction ratio:
42/16 (2.625)
Transmission type:
V-belt automatic
Operation:
Centrifugal automatic type
Chassis:
Frame type:
Aluminum die-cast and steel tube back-
bone
Caster angle:
27.00 °
Trail:
100.0 mm (3.94 in)
Front tire:
Type:
Tubeless
Size:
120/80-14M/C 58S
Manufacturer/model:
IRC/MB67
Manufacturer/model:
DUNLOP/D305FL
Rear tire:
Type:
Tubeless
Size:
150/70-13M/C 64S
Manufacturer/model:
IRC/MB67
Manufacturer/model:
DUNLOP/D305L
Loading:
Maximum load:
YP400 189 kg (417 lb)
YP400A 185 kg (408 lb)
* (Total weight of rider, passenger, cargo
and accessories)
Tire air pressure (measured on cold
tires):
Loading condition:
0–90 kg (0–198 lb)
Front:
200 kPa (29 psi) (2.00 kgf/cm
2
)
Rear:
250 kPa (36 psi) (2.50 kgf/cm
2
)
Loading condition:
YP400 90–189 kg (198–417 lb)
YP400A 90–185 kg (198–408 lb)
Front:
200 kPa (29 psi) (2.00 kgf/cm
2
)
Rear:
250 kPa (36 psi) (2.50 kgf/cm
2
)
Front wheel:
Wheel type:
Cast wheel
Rim size:
14M/C x MT3.00
Rear wheel:
Wheel type:
Cast wheel
Rim size:
13M/C x MT4.00
Front brake:
Type:
Dual disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4
Rear brake:
Type:
Single disc brake
Operation:
Left hand operation
Recommended fluid:
DOT 4
Front suspension:
Type:
Telescopic fork
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
120.0 mm (4.72 in)
Rear suspension:
Type:
Unit swing
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
104.0 mm (4.09 in)
Electrical system:
Ignition system:
Transistorized coil ignition (digital)
Charging system:
AC magneto
SPECIFICATIONS
8-3
1
2
3
4
5
6
7
8
9Battery:
Model:
GT9B-4
Voltage, capacity:
12 V, 8.0 Ah
Headlight:
Bulb type:
Halogen bulb
Bulb voltage, wattage
×
quantity:
Headlight:
12 V, 60 W/55.0 W
×
2
Tail/brake light:
LED
Front turn signal light:
12 V, 21.0 W
×
2
Rear turn signal light:
12 V, 21.0 W
×
2
Auxiliary light:
12 V, 5.0 W
×
2
License plate light:
12 V, 5.0 W
×
1
Meter lighting:
12 V, 2.0 W
×
3
High beam indicator light:
12 V, 1.4 W
×
1
Turn signal indicator light:
12 V, 1.4 W
×
2
Engine trouble warning light:
12 V, 1.4 W
×
1
ABS warning light:
YP400A 12 V, 1.4 W
×
1
Immobilizer system indicator light:
LED
Fuses:
Main fuse:
40.0 A
Headlight fuse:
25.0 A
Signaling system fuse:
10.0 A
Ignition fuse:
10.0 A
Radiator fan fuse:
10.0 A
Hazard fuse:
10.0 A
Fuel injection system fuse:
10.0 A
ABS control unit fuse:
YP400A 10.0 A
ABS motor fuse:
YP400A 30.0 A
Backup fuse:
10.0 A
INDEX
A
ABS (for ABS models) .............................3-12
ABS warning light (for ABS models) ..........3-4
Acceleration and deceleration ...................5-2
Air filter elements and check hoses and
V-belt case air filter element ..................6-19
Anti-theft alarm (optional) ..........................3-9
Auxiliary light bulb, replacing ...................6-38
B
Battery .....................................................6-32
Brake fluid, changing ...............................6-28
Brake fluid level, checking .......................6-27
Brake lever, front .....................................3-11
Brake lever, rear ......................................3-11
Brake levers, lubricating ..........................6-29
Braking ......................................................5-2
C
Cables, checking and lubricating .............6-28
Care ...........................................................7-1
Catalytic converters .................................3-14
Centerstand and sidestand, checking and
lubricating ..............................................6-29
Coolant ....................................................6-17
Cowlings and panels, removing and
installing ..................................................6-7
D
Dimmer switch .........................................3-10
E
Engine break-in .........................................5-4
Engine oil and oil filter element ................6-13
Engine stop switch...................................3-10
Engine trouble warning light ......................3-4
F
Final transmission oil ...............................6-16Front and rear brake lever free play ........ 6-25
Front and rear brake pads, checking....... 6-26
Front fork, checking ................................. 6-30
Fuel ......................................................... 3-14
Fuel consumption, tips for reducing .......... 5-3
Fuel tank cap ........................................... 3-13
Fuses, replacing ...................................... 6-33
H
Handlebar switches ................................... 3-9
Hazard switch .......................................... 3-10
Headlight bulb, replacing ......................... 6-35
High beam indicator light ........................... 3-3
Horn switch.............................................. 3-10
I
Identification numbers ............................... 9-1
Ignition circuit cut-off system ................... 3-20
Immobilizer system.................................... 3-1
Immobilizer system indicator light ............. 3-4
Indicator and warning lights....................... 3-3
K
Key identification number .......................... 9-1
L
License plate light bulb, replacing ........... 6-38
M
Main switch/steering lock .......................... 3-2
Matte color, caution ................................... 7-1
Model label ................................................ 9-2
Multi-function display ................................. 3-5
P
Parking ...................................................... 5-4
Part locations............................................. 2-1
Pass switch ............................................. 3-10
Periodic maintenance and lubrication
chart ........................................................ 6-3Pre-operation check list............................. 4-2
R
Rear brake lock lever .............................. 3-11
Rear brake lock lever cable, adjusting .... 6-26
Rider seat, adjusting ............................... 3-16
S
Safe-riding points ...................................... 1-4
Safety information ..................................... 1-1
Seats ....................................................... 3-15
Shock absorber assemblies, adjusting.... 3-18
Sidestand ................................................ 3-19
Spark plug, checking ............................... 6-11
Specifications ............................................ 8-1
Speedometer............................................. 3-5
Starting off ................................................. 5-2
Starting the engine .................................... 5-1
Start switch.............................................. 3-10
Steering, checking................................... 6-31
Storage...................................................... 7-3
Storage compartments ............................ 3-17
T
Tachometer ............................................... 3-5
Tail/brake light ......................................... 6-36
Throttle cable free play, checking ........... 6-22
Throttle grip and cable, checking and
lubricating ............................................. 6-29
Tires ........................................................ 6-22
Tool kit....................................................... 6-1
Troubleshooting ...................................... 6-39
Troubleshooting charts............................ 6-40
Turn signal indicator lights ........................ 3-3
Turn signal light bulb (front), replacing .... 6-36
Turn signal light bulb (rear), replacing..... 6-37
Turn signal switch ................................... 3-10