Yamaha 2004 YP400 Service Manual page 391

EAS00809
4. Radiator fan motor
• Disconnect the radiator fan motor coupler
from the wire harness.
• Connect the battery (DC 12 V) as shown.
Positive battery lead → blue 1
Negative battery lead → black 2
• Does the radiator fan motor turn?
YES
NO
The radiator fan
motor is faulty and
must be replaced.
COOLING SYSTEM
5. Radiator fan motor relay
• Remove the radiator fan motor relay.
• Connect the pocket tester (Ω × 1) and bat-
tery (12 V) to the radiator fan motor terminal
as shown.
• Check the radiator fan motor relay of conti-
nuity.
Positive battery terminal → red/white 1
Negative battery terminal →
Positive tester probe → brown 3
Negative tester probe → blue 4
• Does the radiator fan motor relay have con-
tinuity between brown and blue?
8 - 47
ELEC
green/yellow 2
YES
Replace the radiator
fan motor relay.
– +
NO