1999 YAMAHA YZF-R7 check engine

8 - 23
–+ELECSIGNALING SYSTEM
NOTE:
• Before troubleshooting, remove the following part(-s):
1) fuel tank
2) bottom cowling
3) front cowling
4) rear cowling
• Troubleshoot with the following special tool(-s).
Pocket tester
90890-03112
CHECKING THE RELAY UNIT
• Remove the relay unit from the coupler.
• Connect the pocket tester (W ´ 1) to the
relay unit terminals as shown.
• Check the starting circuit cutoff relay for
continuity.
NOTE:
When you switch the tester’s positive and
negative probes, the readings in the above
chart will be reversed.
• Are the tester readings correct?
Yes ® Good.
No ® Replace.
CHECKING THE OIL LEVEL SWITCH
• Drain the engine oil.
• Remove the oil level switch.
• Connect the pocket tester (W ´ 1) to the oil
level switch connector as shown.
• Check the oil level switch for continuity as
follows.
• Are the oil level switch readings correct?
Yes ® Good.
No ® Replace. Tester positive probe ®
sky blue 1
Tester negative probe ®
blue/red 2Continu-
ity
Tester positive probe ®
blue/red 2
Tester negative probe ®
sky blue 1No conti-
nuity
Tester positive probe ® white 1
Tester negative probe ® ground
Oil level switch float posi-
tion is upper .Continu-
ity
Oil level switch float posi-
tion is lower õ.No conti-
nuity
R/B L/WW G
Lg
L/R L/BSbB/Y B B/R L/Y
1 2
W
W
õ
11

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–+ELECCOOLING SYSTEM
TROUBLESHOOTING
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
NOTE:
• Before troubleshooting, remove the following part(-s):
1) bottom cowling
2) front cowling
3) rear cowling
• Troubleshoot with the following special tool(-s).
• The radiator fan motor fails to turn.
• The coolant temperature meter needle fails to move when the engine is warm.
Check the main and radiator fan
motor fuses for continuity.Replace.
Check the condition of the bat-
tery.Recharge or replace.
Check the main switch. Replace.
Check the radiator fan motor. Replace.
Check the thermo switch. Replace.
Check the entire cooling system’s
wiring.Repair or replace.
Pocket tester
90890-03112
No good
No good
No good
No good
No good
No good

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–+ELECELECTRONIC FUEL INJECTION SYSTEM
1Main switch
5Battery
6Main fuse
CCamshaft sensor
DThrottle position sensor
EIntake air pressure sensor
FAtmospheric pressure sensor
GIntake air temperature sensor
HCoolant temperature sensor
IPickup coil
JECU
KCylinder #1-injector 1
LCylinder #2-injector 1
MCylinder #3-injector 1
NCylinder #4-injector 1
OCylinder #1-injector 2
PCylinder #2-injector 2
QCylinder #3-injector 2
RCylinder #4-injector 2
XFall detection switch
YSpeed sensor
yFuel pump
zMain relay
}Engine stop switch
ŒElectronic fuel injection system fuse
£ECU fuse
TROUBLESHOOTING
NOTE:
• Before troubleshooting, remove the following part(-s):
1) bottom cowling
2) front cowling
• Troubleshoot with the following special tool(-s).
The condition code is displayed by the tachometer.
Check the condition code list to
identify the faulty part. Refer to
“ELECTRICAL CONTROL SYS-
TEM”.
In diagnosis mode, select the
appropriate diagnosis code to
check the operation of the faulty
part.Check the
wiring.Replace.
Co, diagnosis switch box
90890-03171
Test coupler adapter
90890-03149
Out of specifi-
cationNo good

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–+ELECELECTRICAL CONTROL SYSTEM
CO EMISSION ADJUSTMENT MODE
With the CO emission adjustment mode,
the amount of fuel injected by the injector
can be adjusted.
NOTE:
Prior to adjusting the CO emission, the
throttle bodies must be properly synchro-
nized.
• Remove the bottom cowling and front
cowling.
Refer to “COWLINGS” in chapter 3.
• Remove the CO check bolts from the
exhaust pipe assembly.
• Install the exhaust attachment 1 and CO
tester 2 to the exhaust pipe assembly.
• Attach the engine tachometer to the igni-
tion coil for cylinder #1.
Refer to “SYNCHRONIZING THE THROT-
TLE BODIES” in chapter 3.
• Remove the protection cap 3 from the EFI
test coupler 4.
• Connect the CO, diagnosis switch box 5
to the EFI test coupler 4.
• Start the engine and let it warm up for
several minutes.
Exhaust attachment
90890-03134
Engine tachometer
90890-06760
CO, diagnosis switch box
90890-03171
Engine idling speed
1,000 ~ 1,200 r/min
2