1999 YAMAHA YZF-R7 ECU

7 - 74
CHAS
EB705100
REMOVING THE LOWER BRACKET
1. Stand the motorcycle on a level surface.
WARNINGWARNING
Securely support the motorcycle so that
there is no danger of it falling over.
2. Remove:
• lower ring nut 1
(with the special tool 2)
WARNINGWARNING
Securely support the lower bracket so
that there is no danger of it falling.
Ring nut wrench
90890-01403
EB705401
CHECKING THE STEERING HEAD
1. Wash:
• bearing balls
• bearing races
Recommended cleaning solvent
Kerosine
2. Check:
• bearing balls 1
• bearing races 2
Damage/pitting ® Replace.
3. Check:
• upper bracket
• lower bracket
(along with the steering stem)
Bends/cracks/damage ® Replace.
STEERING HEAD

7 - 78
CHAS
EB706204
REMOVING THE REAR SHOCK ABSORBER
ASSEMBLY
1. Stand the motorcycle on a level surface.
WARNINGWARNING
Securely support the motorcycle so that
there is no danger of it falling over.
NOTE:
Place the motorcycle on a suitable stand
so that the rear wheel is elevated.
2. Remove:
• rear shock absorber assembly lower
bolt 1
• connecting arm-to-swingarm bolt 2
NOTE:
While removing the rear shock absorber
assembly lower bolt, hold the swingarm
so that it does not drop down.
2
2
2
2

1

1

3. Remove:
• rear shock absorber assembly upper
bolt 1
• rear shock absorber assembly
NOTE:
Raise the swingarm and then remove
the rear shock absorber assembly from
between the swingarm.
1
1

EB706401
CHECKING THE REAR SHOCK ABSORBER
ASSEMBLY AND GAS CYLINDER
1. Check:
• rear shock absorber rod
Bends/damage ® Replace the rear
shock absorber assembly.
• rear shock absorber
Gas leaks/oil leaks ® Replace the rear
shock absorber assembly.
• spring
Damage/wear ® Replace the rear
shock absorber assembly.
• gas cylinder
Damage/gas leaks ® Replace.
• bushings
Damage/wear ® Replace.
• dust seals
Damage/wear ® Replace.
• bolts
Bends/damage/wear ® Replace.
REAR SHOCK ABSORBER ASSEMBLY

7 - 82
CHAS
EB707100
NOTE:
Before removing the drive sprocket,
drive chain, and rear wheel, measure the
drive chain slack and the length of a ten-
link section of the drive chain.
EB707111
REMOVING THE SWINGARM
1. Stand the motorcycle on a level surface.
WARNINGWARNING
Securely support the motorcycle so that
there is no danger of it falling over.
NOTE:
Place the motorcycle on a suitable stand
so that the rear wheel is elevated.
2. Measure:
• swingarm side play
• swingarm vertical movement
t t t t t t t t t t t t t t t t t t t t t t t t t t t
a. Measure the tightening torque of the
pivot shaft nut.
b. Measure the swingarm side play
by moving the swingarm from side to
side.
c. If the swingarm side play is out of
specification, check the spacers, bear-
ings, washers, and dust covers.
d. Check the swingarm vertical move-
ment
õ by moving the swingarm up
and down.
If swingarm vertical movement is not
smooth or if there is binding, check the
spacers, bearings, washers, and dust
covers.
s s s s s s s s s s s s s s s s s s s s s s s s s s s
T R..
Pivot shaft nut
125 Nm (12.5 m • kg, 90 ft • lb)
Swingarm side play (at the
end of the swingarm)
1.0 mm (0.04 in)
SWINGARM AND DRIVE CHAIN

8 - 1
–+ELEC

ELECTRICAL COMPONENTS
EB800000
ELECTRICAL
ELECTRICAL COMPONENTS
1
Wire harness
2
Main switch
3
Front brake light switch
4
Ignition coils
5
Clutch switch
6
Throttle position sensor
7
Intake air temperature sensor
8
Intake air pressure sensor
9
Atmospheric pressure sensor
0
Turn signal relay
A
Relay unit
B
ECU
C
CDI unit
D
Fuse box
E
Fall detection switch
F
Starter relay
G
Main fuse
H
Main relay
I
Battery
J
Rectifier/regulator
K
Rear brake light switch
L
Neutral switch
M
Speed sensor
N
Sidestand switch
O
Stator coil assembly
P
Oil level switch
Q
Pickup coil
R
Radiator fan
S
Horn
T
Coolant temperature
sender
U
Thermo switch
V
Camshaft sensor
8

8 - 7
–+ELECIGNITION SYSTEM
EB802001
IGNITION SYSTEM
CIRCUIT DIAGRAM
B
(BLACK) (DARK GRAY)
(BLACK)B
L
B
L
K
WWW
86
7RR
Br
BBRR
L/W BrL/W
RR
R
B
B
BBB
B
R
WWW(BLACK)
L/W
B
R/B
R/L
G/B
R/L
L/W
B (BLUE)
Gy
Gy/B
B
B(BLUE)
Gy
B
Br
G
L/R
B
Br
G L/R
B
Br/W
Br
B
B
B
B
L/WBr
R/W
G/Y R/W
B/WB/L(GRAY)
(BROWN)
h
Br
YB
BBr
Y (BROWN) (BROWN)
R/YLBr/WP
B(BLUE) (BLUE)(BLACK) (BLACK)
Br
BBR/WR/B
Y
P
ON OFF
R
RL/R
LBr/L
B
R/L
G/W(BLACK)
R/L R/BR/G L/R(GREEN)
(BLACK) (BLACK)(BLACK)(BLACK)
O Gy
B
Br/G
B Br
L/G W/G
Y/G
BYL
B
B
G
Ch Dg
BL/W
L/R
R/BB/Y
L/YSb
R/L R/B
Br/WB1G/W B/L
L/Y
W
B/L
W/B L/YB/L
W/YL/Y
L/Y
Br L
R
Br/LR
Br/L
L/W
L/Y
Br
L/W
L/Y L/B
L L/R
B L/Y
L/R LB B BB
W
WW
W
WW
B
BB
B
B B1
B
BB
B
B
B/YL/Y
B/YL/Y
R/Y
L P
B Br/WDg
ChB/YYG
L/Y
Ch
B/YDg
G
L/YY
B
R
G
B/L
YLWBYPBL
GBB/W
(BLACK)YB
BCh
(BLACK)BDg
B
(GRAY)(BLACK)
(BLACK)
(BLACK) (GRAY)
(GRAY)
(GRAY)
(GRAY) (GRAY)B/W B/L
B/L B/L
W/LP/B Y/L
R
B
PASS
(BLACK)
(BLACK)ChB
(BLACK)DgB
N
B(BLACK)B
(BLACK) (BLACK)
O/G B(BLACK) (BLACK)
L
R/L G/B
M
R/L L/B
N
R/LR/L O/B
OY
Y/R C YG/R C GBr/R C BrGy/R C Gy
R R/LRRRRY
P
RG G(BROWN)
Q
RBr Br
Gy(DARK GRAY)R(GRAY)
R
R/YLg/Y
R/Y Lg/Y R/WB/L
R/Y
R
Y/L
B
L/R
YL/R
Gy/B
Gy
G/WB1
W/Y
W1
L/R B/L
YLW/B
Y/L W/L
P/W P/LR/Y
Br/W R/W
Lg/YL/W B/W
R/L
R/B L/WW G
Lg
L/R L/BSb
B/Y B B/R L/Y
RBR
R/G
4
BL/Y
BB
Br/L
BrBrL
B
B
B
B
BR/GB1
B
Y
B
R/WR/B
R/GR/BL/RR/L
Br
G/WR/L
L/YW/BB/L
GyGy/B
R/L
L/R
L/W
B/LL
B
Br/W
Br
Y
LPWP
B2
B2
R PB
(BLACK)
B3
B3W2
Y/G L/GBr/G Br/R
Gy/R
BrBrO/B
G/Y L/B G/B G/R
Y/R
W/G Y/B R/B
O/B
R/L
L/B
GyO
O Lg/R
B
B
B
BB Gy
Gy/G Gy/G Gy/G
O/G O/GO/G
Gy GyGy/G
Br/G
W/G
Y/G
L/G
Br
WW/YB/L
L/Y
Lg/RG/Y W/YL/R
Y/B
L/YBSb
Sb
R/GG/WWYChL
W
BrP
P G Y Ch Dg B
Dg
B
BBBB
B
Dg
ChBr
LR/Y
L/Y B/Y
Br/LBr/LBr/L
BrR/YR/W
B2
Gy/BB3
R/B
G/B
L/B
O/B
Gy/R
Lg/RY/R
G/R
Br/R
R/W
R/Y
Lg/Y
W1
W2
(BLACK)
(BLACK)
(BLACK)
(BLACK) (GRAY)
B
L
B
B/L
Br/W
B/LG/W
S
T
U
V W J
Z
R/G
B L/Y
W/YG/Y W Y/B
Br
G/WLg/R Lg Y
ChDg
L
gf f e dc b a` ] \[ FE DC
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(BLACK)
Y
L/W
Y/B
G/Y
Y/L
W/L
P/BR
B3 W/B
B/L
L
Y
P/W
P/L
Br
G/W
B/W
W/Y
Br
B2
|
~
z } {
L/Y
A
A
A
A
AA
AAAA
A C
A
A
A
A A
A
P/LP/W
BB/L BB/L
DL DL
C
W/LP/B
WIRE HARNESS SUB LEAD
B/L B/L
BB
R/L R/L L
R/L R/L L
LRR
LR
R(GRAY)
(GRAY)
WIRE HARNESS SUB LEADY/R
Br/RP/W
G/R Gy/R P/L
WYBr
PG
Gy(BLACK)
(BLACK)
WIRE HARNESS SUB LEAD HEADLIGHT AND METER SUB-WIRE HARNESS
(BLACK)
(BLACK)
WIRE HARNESS
Y W/Y G/WG/W
R/G L G/Y Dg
Br
GY
G L/YW/Y
L/Y BBr
B W Y/B Lg Lg/RCh L/R
L/R
G/Y
R/GDg
L
Lg/R
Lg
W
Y/B ChA
BC
D
D R/L D R/L D R/L D
R
B1
Br/G
W/G
Y/G
L/G
Br
Gy
TCylinder #2-ignition coil
UCylinder #3-ignition coil
VCylinder #4-ignition coil
WCDI unit
ZNeutral switch
}Engine stop switch
£ECU fuse
1Main switch
5Battery
6Main switch
0Relay unit
ADiode
BSidestand switch
JECU
SCylinder #1-ignition coil

8 - 8
–+ELECIGNITION SYSTEM
TROUBLESHOOTING
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
No good
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK
C0NTINUITYOK The ignition system fails to operate (no spark or intermittent spark).
Check the main and ECU fuses for
continuity.Replace.
Check the condition of the bat-
tery.Recharge or replace.
Check the spark plug. Re-gap or replace.
Measure the ignition spark gap. Ignition system is OK.
Measure the ignition coil resis-
tance.Replace.
Measure the pickup coil resis-
tance.Replace.
Check the main switch. Replace.
Check the engine stop switch.Replace the right handlebar
switch.
Check the neutral switch. Replace.
Check the diode. Replace.
Check the sidestand switch. Replace.
Check the relay unit. Replace.
Check the entire ignition sys-
tem’s wiring.Repair or replace.
Replace the CDI unit.
No good
No good
No good
No good
No good
No good
No good
No good
No good
OK
No good
No good
No good

8 - 9
–+ELECIGNITION SYSTEM
BAD
NOTE:
• Before troubleshooting, remove the following part(-s):
1) fuel tank
2) air filter case
3) bottom cowling
4) front cowling
5) rear cowling
• Troubleshoot with the following special tool(-s).
Replace the ECU.
Ignition checker
90890-06754
Pocket tester
90890-03112
MEASURING THE IGNITION SPARK GAP
The following procedure applies to all of
the spark plugs.
• Disconnect the ignition coil from the spark
plug.
• Connect the ignition checker 1 as shown.
2 Ignition coil
• Set the main switch to “ON”.
• Measure the ignition spark gap a.
• Crank the engine by pushing the start
switch and gradually increase the spark
gap until a misfire occurs.
• Is there a spark and is the spark gap
within specification?
Yes ® Good.
No ® Measure the ignition coil resistance.
Minimum ignition spark gap
6 mm (0.24 in)

8 - 12
–+ELECELECTRIC STARTING SYSTEM
EB803000
ELECTRIC STARTING SYSTEM
CIRCUIT DIAGRAM
B
(BLACK) (DARK GRAY)
(BLACK)B
L
B
L
K
WWW
86
7RR
Br
BBRR
L/W BrL/W
RR
R
B
B
BBB
B
R
WWW(BLACK)
L/W
B
R/B
R/L
G/B
R/L
L/W
B (BLUE)
Gy
Gy/B
B
B(BLUE)
Gy
B
Br
G
L/R
B
Br
G L/R
B
Br/W
Br
B
B
B
B
L/WBr
R/W
G/Y R/W
B/WB/L(GRAY)
(BROWN)
h
Br
YB
BBr
Y (BROWN) (BROWN)
R/YLBr/WP
B(BLUE) (BLUE)(BLACK) (BLACK)
Br
BBR/WR/B
Y
P
ON OFF
R
RL/R
LBr/L
B
R/L
G/W(BLACK)
R/L R/BR/G L/R(GREEN)
(BLACK) (BLACK)(BLACK)(BLACK)
O Gy
B
Br/G
B Br
L/G W/G
Y/G
BYL
B
B
G
Ch Dg
BL/W
L/R
R/BB/Y
L/YSb
R/L R/B
Br/WB1G/W B/L
L/Y
W
B/L
W/B L/YB/L
W/YL/Y
L/Y
Br L
R
Br/LR
Br/L
L/W
L/Y
Br
L/W
L/Y L/B
L L/R
B L/Y
L/R LB B BB
W
WW
W
WW
B
BB
B
B B1
B
BB
B
B
B/YL/Y
B/YL/Y
R/Y
L P
B Br/WDg
ChB/YYG
L/Y
Ch
B/YDg
G
L/YY
B
R
G
B/L
YLWBYPBL
GBB/W
(BLACK)YB
BCh
(BLACK)BDg
B
(GRAY)(BLACK)
(BLACK)
(BLACK) (GRAY)
(GRAY)
(GRAY)
(GRAY) (GRAY)B/W B/L
B/L B/L
W/LP/B Y/L
R
B
PASS
(BLACK)
(BLACK)ChB
(BLACK)DgB
N
B(BLACK)B
(BLACK) (BLACK)
O/G B(BLACK) (BLACK)
L
R/L G/B
M
R/L L/B
N
R/LR/L O/B
OY
Y/R C YG/R C GBr/R C BrGy/R C Gy
R R/LRRRRY
P
RG G(BROWN)
Q
RBr Br
Gy(DARK GRAY)R(GRAY)
R
R/YLg/Y
R/Y Lg/Y R/WB/L
R/Y
R
Y/L
B
L/R
YL/R
Gy/B
Gy
G/WB1
W/Y
W1
L/R B/L
YLW/B
Y/L W/L
P/W P/LR/Y
Br/W R/W
Lg/YL/W B/W
R/L
R/B L/WW G
Lg
L/R L/BSb
B/Y B B/R L/Y
RBR
R/G
4
BL/Y
BB
Br/L
BrBrL
B
B
BR/GB1
B
Y
B
R/WR/B
R/GR/BL/RR/L
Br
G/WR/L
L/YW/BB/L
GyGy/B
R/L
L/R
L/W
B/LL
B
Br/W
Br
Y
LPWP
B2
B2
R PB
(BLACK)
B3
B3W2
Y/G L/GBr/G Br/R
Gy/R
BrBrO/B
G/Y L/B G/B G/R
Y/R
W/G Y/B R/B
O/B
R/L
L/B
GyO
O Lg/R
B
B
B
BB Gy
Gy/G Gy/G Gy/G
O/G O/GO/G
Gy GyGy/G
Br/G
W/G
Y/G
L/G
Br
WW/YB/L
L/Y
Lg/RG/Y W/YL/R
Y/B
L/YBSb
Sb
R/GG/WWYChL
W
BrP
P G Y Ch Dg B
Dg
B
BBBB
B
Dg
ChBr
LR/Y
L/Y B/Y
Br/LBr/LBr/L
BrR/YR/W
Gy/BB3
R/B
G/B
L/B
O/B
Gy/R
Lg/RY/R
G/R
Br/R
R/W
R/Y
Lg/Y
W1
W2
(BLACK)
(BLACK)
(BLACK)
(BLACK) (GRAY)
B
L
B
B/L
Br/W
B/LG/W
S
T
U
V W J
Z
R/G
B L/Y
W/YG/Y W Y/B
Br
G/WLg/R Lg Y
ChDg
L
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(BLACK)
Y
L/W
Y/B
G/Y
Y/L
W/L
P/BR
B3 W/B
B/L
L
Y
P/W
P/L
Br
G/W
B/W
W/Y
Br
B2
|
~
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L/Y
A
A
A
A
AA
AAAA
A C
A
A
A
A A
A
P/LP/W
BB/L BB/L
DL DL
C
W/LP/B
WIRE HARNESS SUB LEAD
B/L B/L
BB
R/L R/L L
R/L R/L L
LRR
LR
R(GRAY)
(GRAY)
WIRE HARNESS SUB LEADY/R
Br/RP/W
G/R Gy/R P/L
WYBr
PG
Gy(BLACK)
(BLACK)
WIRE HARNESS SUB LEAD HEADLIGHT AND METER SUB-WIRE HARNESS
(BLACK)
(BLACK)
WIRE HARNESS
Y W/Y G/WG/W
R/G L G/Y Dg
Br
GY
G L/YW/Y
L/Y BBr
B W Y/B Lg Lg/RCh L/R
L/R
G/Y
R/GDg
L
Lg/R
Lg
W
Y/B ChA
BC
D
D R/L D R/L D R/L D
R
B1
Br/G
W/G
Y/G
L/G
Br
BBB2
GyBSidestand switch
JECU
ZNeutral switch
rClutch switch
}Engine stop switch
~Start switch
£ECU fuse
1Main switch
5Battery
6Main fuse
7Starter relay
8Starter motor
9Diode
0Relay unit
ADiode