Troubleshooting - Yamaha 2004 YP400 Service Manual

EAS00781

TROUBLESHOOTING

Any of the following fail to light: head-
lights, high beam indicator light, taillight,
license plate light, storage box light, aux-
iliary lights or meter light.
Check:
1. main, headlights, signaling system, turn sig-
nal/hazard, and backup fuses
2. battery
3. main switch
4. dimmer switch
5. pass switch
6. storage box light switch
7. headlight relay 1
8. headlight relay 2
9. wiring connections
(of the entire lighting system)
NOTE:
_
• Before troubleshooting, remove the following
part(s):
1. storage box
2. front cowling
3. meter assembly
• Troubleshoot with the following special
tool(s).
Pocket tester
90890-03112, YU-03112-C
EAS00738
1. Main, headlight, signaling system, turn sig-
nal/hazard, and backup fuses
• Check the main, headlight, signaling sys-
tem, turn signal/hazard, and backup fuses
for continuity.
Refer to "CHECKING THE FUSES" in
chapter 3.
• Are the main, headlight, signaling system,
turn signal/hazard, and backup fuses OK?
YES
NO
Replace the fuse(s).
LIGHTING SYSTEM
EAS00739
2. Battery
• Check the condition of the battery.
Refer to "CHECKING AND CHARGING
THE BATTERY" in chapter 3.
Minimum open-circuit voltage
12.8 V or more at 20 °C (68 °F)
• Is the battery OK?
EAS00749
3. Main switch
• Check the main switch for continuity.
Refer to "CHECKING THE SWITCHES".
• Is the main switch OK?
EAS00784
4. Dimmer switch
• Check the dimmer switch for continuity.
Refer to "CHECKING THE SWITCHES".
• Is the dimmer switch OK?
8 - 27
ELEC
YES
• Clean the battery
terminals.
• Recharge or
replace the battery.
YES
Replace the
switch/immobilizer
unit.
YES
The dimmer switch is
faulty. Replace the
left handlebar switch.
– +
NO
NO
main
NO