Yamaha YZF-R1 1998 Service Manual page 404

EB812010
TROUBLESHOOTING
The tachometer starts to display the self-
diagnosis sequence.
Check:
1. throttle position sensor
2. Exup
3. fuel level indicator light
NOTE:
• Before troubleshooting, remove the
following part(-s):
1) rider seat
2) fuel tank
3) air filter case
• Troubleshoot with the following spe-
cial tool(-s).
Pocket tester
90890-03112
EB812020
1. Throttle position sensor
CIRCUIT DIAGRAM
B/L B/R B
G/Y Sb B/Y R/W
Gy W
W/R Y
B/R L Y/L B/R
B/Y B/L W/B B/Y
E
B/L
F
L
Y
L Y B/L
B/L
F Throttle position sensor
G Ignitor unit
B
R/B R/B
Y/B O
R/W
L/R Gy
B
O
L
L/R
G/Y
B/Y
Gy
B/R
G
L L
W/R
B/L
Y
Gy
B Y/B Sb
W B
SELF-DIAGNOSIS
1.Wire harness
• Check the wire harness for continuity.
Refer to "CIRCUIT DIAGRAM".
• Is the wire harness OK?
EB812401
2.Throttle position sensor
• Check the throttle position sensor for
continuity.
Refer to "CHECKING AND ADJUSTING
THE THROTTLE POSITION SENSOR" in
chapter 6.
• Is the throttle position sensor OK?
Replace the ignitor
unit.
R/B
B
O
R/B
B
Gy
Gy
B/L
8 - 58
ELEC
YES
Repair or
the wire harness.
YES
Replace the throt-
tle position sensor.
– +
NO
replace
NO