1999 YAMAHA YZF-R7 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

8 - 25
–+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

8 - 29
–+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

8 - 30
–+ELECELECTRICAL CONTROL SYSTEM
ELECTRICAL CONTROL SYSTEM
The YZF-R7 features an electrical control system with the following modes:
• user mode
• diagnosis mode
• CO emission adjustment mode
NOTE:
The vehicle is normally in user mode. Special tools are needed to switch to a diagnosis mode
or to the CO emission adjustment mode.
USER MODE
• If a circuit is defective, setting the main switch to “ON” (without starting the engine) will
cause the corresponding condition code to be displayed by the tachometer, the warning
light to light up, and the engine trouble symbol to blink. When the engine is started, the
condition code is no longer displayed and the engine speed appears.
• Normally, when the main switch is set to “ON”, the warning light comes on for 1.4 seconds
and then goes off. The warning light also comes on while the start switch is pushed.
• When the engine is not running, the warning light flashes once every 0.16 second if the start
switch is pushed under the following conditions.
• The fall detection switch switches off the main relay.
• Ignition is cut off by the sidestand switch.
• The injector operating voltage decreases to 3 V or less, or the main relay malfunctions.
• The pickup coil is defective.
• The fall detection switch is defective.

8 - 31
–+ELECELECTRICAL CONTROL SYSTEM
Tachometer display sequence (engine not running)
110,000 r/min for 2.0 seconds
2First condition code (13 = intake air pressure sensor)
3Second condition code (42 = speed sensor)
41st digit of condition code for 1.0 second
510,000 r/min for 0.5 second
62nd digit of condition code for 1.0 second
510Time
(seconds) 5
0 10 Revolution
(´10
3r/min)
46
5
1246
511 3Repeat
Main switch is turnd on

8 - 32
–+ELECELECTRICAL CONTROL SYSTEM
Condition code list
NOTE:
* This condition code is also displayed in the following cases:
- when the starter switch is held down for more than 4 seconds, causing the warning
light to flash
- when the ignition circuit cut-off system stops the engine or prevents it from starting
** This condition code is also displayed when the engine is operated at 5,000 r/min for at
least 30 seconds with the rear wheel at standstill.
*** This condition code is also displayed when the engine stop switch is turned to “ ”
while riding with the transmission in gear. Condition
codeCircuit Defect(s) System response
11 Camshaft sensor • No incoming sig-
nalThe ECU pairs the ignition of cyl-
inders #1 and #4 and cylinders #2
and #3. The motorcycle can be
ridden.
12* Pickup coil • No incoming sig-
nalThe motorcycle cannot be ridden.
13 Intake air pressure
sensor• Disconnected
• Short-circuitThe ECU stays set to an intake air
pressure of 760 mm Hg (29.9 in Hg).
The motorcycle can be ridden.
14 Intake air pressure
sensor hose and
negative pressure
hose• Improper connec-
tion
• Bending
15 Throttle position
sensor• Disconnected
• Short-circuitThe ECU stays set to a wide throt-
tle opening.
The motorcycle can be ridden.
16 Throttle position
sensor• Locked
21 Coolant tempera-
ture sensor• Disconnected
• Short-circuitThe ECU stays set to a coolant
temperature of 80˚C (176˚F).
The motorcycle can be ridden.
22 Intake air tempera-
ture sensor• Disconnected
• Short-circuitThe ECU stays set to an intake air
temperature of 40˚C (104˚F).
The motorcycle can be ridden.
23 Atmospheric pres-
sure sensor• Disconnected
• Short-circuitThe ECU stays set to an atmo-
spheric pressure of 760 mm Hg
(29.9 in Hg).
The motorcycle can be ridden.
41 Fall detection
switch• Disconnected The main relay stays switched off.
The motorcycle cannot be ridden.
42** Speed sensor • Incorrect signal The ECU stays set to 6th gear.
The motorcycle can be ridden.
43*** Monitored voltage • Incorrect The ECU stays set to a monitored
voltage of 12 V.
The motorcycle can be ridden.
44 ROM operation • CO emission
adjustment errorThe CO emission adjustment is
set to 0.

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–+ELECELECTRICAL CONTROL SYSTEM
DIAGNOSIS MODE
There are two operation methods for this mode: one is performed using the CO, diagnosis
switch box, the other is performed using the test coupler adapter. With the CO, diagnosis
switch box method, the switches on the CO, diagnosis switch box are used. With the test cou-
pler adapter method, the start switch and the engine stop switch are used. The procedures for
selecting and using each method is explained below.
NOTE:
The engine cannot be started, the vehicle cannot be ridden, and no other mode can be
selected while either of the diagnosis mode operation methods is being performed.
CO, diagnosis switch box method
• Remove the bottom cowling and the front
cowling.
Refer to “COWLINGS” in chapter 3.
• Remove the protection cap 1 from the EFI
test coupler 2.
• Connect the CO, diagnosis switch box 3
to the EFI test coupler 2.
• Turn the main switch to “ON”.
• Turn the engine stop switch to “ ”.
• Within 4 seconds, press the following
switches on the CO, diagnosis switch box
in the order indicated to enter the diagno-
sis mode.
4MODE switch = 1
5UP switch = 2
6DOWN switch = 3
1 ® 2 ® 1 ® 3 ® 1 ® 2 ® 1 ® 3 ® 1 ® 2 ®
1 ® 3
The warning light flashes when the unit has
entered the diagnosis mode.
NOTE:
Turn the main switch to “OFF” to cancel the
diagnosis mode.
CO, diagnosis switch box
90890-03171

8 - 35
–+ELECELECTRICAL CONTROL SYSTEM
Test coupler adapter method
• Remove the bottom cowling and the front
cowling.
Refer to “COWLINGS” in chapter 3.
• Remove the protection cap 1 from the EFI
test coupler 2.
• Connect the test coupler adapter 3 to the
EFI test coupler 2.
• Disconnect the fuel pump coupler from
the wire harness.
• Turn the main switch to “ON”.
• Turn the engine stop switch to “ ”.
• Press the start switch ten times within 4
seconds to enter the diagnosis mode.
The warning light flashes when the unit
has entered the diagnosis mode.
NOTE:
Turn the main switch to “OFF” to cancel the
diagnosis mode.
Operation after entering the diagnosis
mode
• Select a diagnosis code by pressing the
start switch. Refer to the diagnosis code
list.
First, press the start switch once to select
diagnosis code 01. Afterwards, each press
of the start switch increases the diagnosis
code number by one. If diagnosis code 31
is selected, pressing the start switch once
selects diagnosis code 00.
• Turn the engine stop switch to “ ” to
start the test for the selected diagnosis
code.
NOTE:
To select another diagnosis code, turn the
engine stop switch to “ ”, and then press
the start switch.
Example:
First, select diagnosis code 29 as follows.
• Turn the engine stop switch to “ ”.
• Press the start switch 29 times.
• Turn the engine stop switch to “ ”.
Next, select diagnosis code 10 as follows.
• Turn the engine stop switch to “ ”.
• Press the start switch 13 times.
• Turn the engine stop switch to “ ”.
Test coupler adapter
90890-03149