Yamaha YZF-R1 98, Service Manual

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ELEC
SIGNALING SYSTEM
EB806410
CHECKING THE SIGNALING SYSTEM
1. The horn fails to sound.
YES NO
1.Horn sw itch
• Check the horn sw itch for continuity.
Refer to “ CHECKING THE SWITCHES” .
• Is the horn sw itch OK?
Replace the left han-
dlebar sw itch.
YES
NO
2.Voltage
• Connect the pocket tester (DC 20V) to
the horn connector at the horn term inal
as show n.
Tester positive probe
→
black/ w hite 1
Tester negative probe
→
ground
• Set the m ain sw itch to “ ON” .
• Push the horn sw itch.
• M easure the voltage (12V) of black/w hite
at the horn term inal.
• Is the voltage w ithin specification?
The w iring circuit
from the m ain
sw itch to the horn
connector is faulty
and m ust be
repaired.
NO
YES
3.Horn
• Disconnect the black connector at the
horn term inal.
• Connect a jum per lead 1 to the horn ter-
m inal and ground the jum per lead.
• Set the m ain sw itch to “ ON” .
• Push the horn sw itch.
• Does the horn sound?
The horn is OK.
YES
NO
4.Voltage
• Connect the pocket tester (DC 20V) to
the horn connector at the black term inal
as show n.
Tester positive probe
→
black 1
Tester negative probe
→
ground
• Set the m ain sw itch to “ ON” .
• M easure the voltage (12V) of black
1 at
the horn term inal.
• Is the voltage w ithin specification?
Repair or replace
the horn. Replace the horn.