Checking The Lighting System - Yamaha 2004 YP400 Service Manual

EAS00788

CHECKING THE LIGHTING SYSTEM

1. The headlights and the high beam indicator
light fail to come on.
1. Headlight bulb and socket
• Check the headlight bulb and socket for
continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS"
• Are the headlight bulb and socket OK?
YES
2. High beam indicator light bulb and socket
• Check the high beam indicator light bulb
and socket for continuity.
Refer to "CHECKING THE BULBS AND
BULB SOCKETS".
• Is the high beam indicator light bulb and
socket OK?
YES
3. Voltage
• Connect the pocket tester (DC 20 V) to the
headlight and meter assembly couplers as
shown.
NO
Replace the head-
light bulb, socket or
both.
NO
Replace the high
beam indicator light
bulb, socket or both.
LIGHTING SYSTEM
È When the dimmer switch is set to "
É When the dimmer switch is set to "
Headlight
Positive tester probe →
Negative tester probe → black 3
Headlight coupler
DC 20V
High beam indicator light
Positive tester probe → yellow 4
Negative tester probe → black 5
Meter assembly coupler
Ch Dg
G/L
• Set the main switch to "ON".
• Start the engine.
• Set the dimmer switch to "
• Measure the voltage (DC 12 V) of yellow
1 (green 2) on the headlight coupler and
yellow 4 on the meter assembly coupler
(wire harness side).
• Is the voltage within specification?
This circuit is OK.
8 - 30
ELEC
yellow 1 or green 2
È
G
+
Y B
É
1
Y R/W R/G G
L Y/L B/L Gy B
4
" or "
YES
The wiring
from the main switch
to the headlight cou-
pler or meter assem-
bly coupler is faulty
and must
repaired.
– +
"
"
2
3
5
".
NO
circuit
be