Yamaha YP400T Service Manual page 359

5. Storage box light switch
• Check the storage box light switch for con-
tinuity.
Refer to "CHECKING THE SWITCHES".
• Is the storage box light switch OK?
YES
6. Headlight relay 1
• Remove the headlight relay 1.
• Connect the pocket tester (Ω × 1) and bat-
tery (12 V) to the headlight relay 1 terminals
as shown.
• Check the headlight relay 1 for continuity.
Positive battery terminal → red/yellow 1
Negative battery terminal → white/black 2
Positive tester probe → red/yellow 3
Negative tester probe → green/blue 4
3
4
2
1
W/B R/Y
G/L
R/Y
• Does the headlight relay 1 have continuity
between red/yellow and green/blue?
YES
NO
The storage box light
switch is faulty.
Replace the storage
box light switch.
+
NO
Replace the head-
light relay 1.
8 - 28
LIGHTING SYSTEM
7. Headlight relay 2
• Remove the headlight relay 2.
• Connect the pocket tester (Ω × 1) and bat-
tery (12 V) to the headlight relay 2 terminal
as shown.
• Check the headlight relay 2 for continuity.
Positive tester probe → green/blue 1
Negative tester probe → green 2
1
2
Positive battery terminal → green/black 3
Negative battery terminal → black 4
Positive tester probe → green/blue 5
Negative tester probe → yellow 6
5
6
4
3
B G G/B
Y
G/L
• Does the headlight relay 2 have continuity
between green/blue and green or yellow?
YES
–
ELEC
B G G/B
Y
G/L
+
NO
Replace the head-
light relay 2.
+