Yamaha Mt 01 T 2005 Manual

							FUEL INJECTION SYSTEM
7-36
Sensor operation tableEr-4Non-registered data has 
been received from the 
meter.Improper connection in wire harness.
Malfunction in meter.
Malfunction in ECU.—
Diag-
nostic 
code 
No.Item Meter display Checking method
01 Throttle angle
Fully closed position 15–20 Check with throttle fully 
closed.
Fully opened position 95–100 Check with throttle fully 
open.
03 Pressure difference
(atmospheric pressure and 
cylinder-#1 intake air 
pressure)Displays the cylinder-#1 
intake air pressure.Set the engine stop switch 
to “”, then operate the 
throttle while pushing the 
start switch “”. (If the 
display value changes, the 
performance is OK.)
04 Pressure difference
(atmospheric pressure and 
cylinder-#2 intake air 
pressure)Displays the cylinder-#2 
intake air pressure.Set the engine stop switch 
to “”, then operate the 
throttle while pushing the 
start switch “”. (If the 
display value changes, the 
performance is OK.)
05 Air temperature Displays the air temperature. Compare the actually 
measured air temperature 
with the meter display 
value.
07 Vehicle speed pulse 0–999 Check that the number 
increases when the rear 
wheel is rotated. The 
number is cumulative and 
does not reset each time 
the wheel is stopped.
08 Lean angle cut-off switch Remove the lean angle cut-
off switch and incline it 
more than 65 degrees. Upright 0.4–1.4
Overturned 3.7–4.4
09 Fuel system voltage
(battery voltage) Approximately 12.0Set the engine stop switch 
to “”, and then compare 
with the actually measured 
battery voltage. (If the 
battery voltage is lower, 
perform recharging.) Fault 
code 
No.Symptom Probable cause of malfunctionDiagnostic 
code No. 
						

							FUEL INJECTION SYSTEM
7-37
11 Engine temperature Displays the engine 
temperature.Compare the actually 
measured engine 
temperature with the meter 
display value.
12 Muffler cooling fan 
temperatureDisplays the muffler cooling 
fan temperature.Compare the actually 
measured muffler cooling 
fan temperature with the 
meter display value.
20 Sidestand switch Set ON/OFF the Sidestand 
switch. (with the 
transmission in gear.) Stand retracted ON
Stand extended OFF
21 Neutral switch Shift the transmission.
Neutral ON
In gear OFF
53 EXUP servo motor Displays the operating angle.
Engine trouble warning light 
comes on twice: once when 
the EXUP valve is closing 
and once when it is opening.—
60 EEPROM fault code 
display—
No history 00
History exists 01 or 02 (Cylinder fault code)
(If both cylinders are 
defective, the display 
alternates every two 
seconds.)
61 Malfunction history code 
display—
No history 00
History exists Fault codes 12-63
(If more than one code 
number is detected, the 
display alternates every two 
seconds to show all the 
detected code numbers. 
When all code numbers are 
shown, the display repeats 
the same process.)
62 Malfunction history code 
erasure
No history 0—
History exists Up to 28 fault codes To erase the history, set the 
engine stop switch to “”. Diag-
nostic 
code 
No.Item Meter display Checking method 
						

							FUEL INJECTION SYSTEM
7-38
Actuator operation table63 Stopping the flashing of the 
engine trouble warning light 
(erasing the muffler cooling 
fan temperature sensor 
fault code)00 To stop the flashing of the 
engine trouble warning 
light, set the engine stop 
switch to “”.
70 Control number 0–255—
Diag-
nostic 
code 
No.Item Actuation Checking method
30Cylinder-#1 left or right 
ignition coilActuates the cylinder-#1 left 
or right ignition coil for five 
times every second.
Illuminates the engine 
trouble warning light.Check the spark five times.
Connect an ignition 
checker.
31 Cylinder-#2 left ignition coilActuates the cylinder-#2 left 
ignition coil for five times 
every second.
Illuminates the engine 
trouble warning light.Check the spark five times.
Connect an ignition 
checker.
32Cylinder-#1 left or right 
ignition coilActuates the cylinder-#1 left 
or right ignition coil for five 
times every second.
Illuminates the engine 
trouble warning light.Check the spark five times.
Connect an ignition 
checker.
33Cylinder-#2 right ignition 
coilActuates the cylinder-#2 right 
ignition coil for five times 
every second.
Illuminates the engine 
trouble warning light.Check the spark five times.
Connect an ignition 
checker.
36 Injector #1Actuates the injector #1 for 
five times every second.
Illuminates the engine 
trouble warning light.Check the operating sound 
of the injector #1 five times.
37 Injector #2Actuates the injector #2 for 
five times every second.
Illuminates the engine 
trouble warning light.Check the operating sound 
of the injector #2 five times.
49 Intake solenoidActuates the intake solenoid 
for five times every second.
Illuminates the engine 
trouble warning light.Check the operating sound 
of the intake solenoid five 
times. Diag-
nostic 
code 
No.Item Meter display Checking method 
						

							FUEL INJECTION SYSTEM
7-39
EAS27460
TROUBLESHOOTING DETAILS
This section describes the measures per fault code number displayed on the meter. Check and service 
the items or components that are the probable cause of the malfunction following the order given.
After the check and service of the malfunctioning part has been completed, reset the meter display ac-
cording to the reinstatement method.
Fault code No.:50 Fuel pump relayActuates the fuel pump relay 
for five times every second.
Illuminates the engine 
trouble warning light.
(The engine trouble warning 
light is OFF when the relay is 
ON, and the engine trouble 
warning light is ON when the 
relay is OFF).Check the operating sound 
of the fuel pump relay five 
times.
51Muffler cooling fan motor 
relayActuates the muffler cooling 
fan motor relay for five cycles 
of five seconds. (ON 2 
seconds, OFF 3 seconds)
Illuminates the engine 
trouble warning light.Check the operating sound 
of the muffler cooling fan 
motor relay five times.
52 Headlight relayActuates the headlight relay 
for five cycles of five 
seconds. (ON 2 seconds, 
OFF 3 seconds)
Illuminates the engine 
trouble warning light.Check the operating sound 
of the headlight relay five 
times.
54 ISC valveActuates and fully closes the 
ISC valve, then opens it to 
the standby opening position 
when the engine is started. 
This operation takes 
approximately 12 seconds 
until it is completed.
Illuminates the engine 
trouble warning light.The ISC unit vibrates when 
the ISC valve operates.
55 Decompression solenoidActuates the decompression 
solenoid for five cycles of five 
seconds. (ON 2 seconds, 
OFF 3 seconds)
Illuminates the engine 
trouble warning light.
NOTE:
Be sure to push the start 
switch, otherwise the above 
mentioned operation will not 
be possible.Check the operating sound 
of the decompression 
solenoid five times.
NOTE:
Disconnect the starter 
motor lead before 
performing this procedure. Diag-
nostic 
code 
No.Item Actuation Checking method 
						

							FUEL INJECTION SYSTEM
7-40
Code number displayed on the meter when the engine failed to work normally. Refer to “Self-Diagnos-
tic Function table”.
Diagnostic code No.:
Diagnostic code number to be used when the diagnostic mode is operated. Refer to “DIAGNOSTIC 
MODE” on page 7-31.
Fault code No. 12 Symptom No normal signals are received from the crankshaft posi-
tion sensor.
Diagnostic code No.——
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Installed condition of crankshaft 
position sensor.Check for looseness or pinching. Cranking the 
engine.
2 Connections
Crankshaft position sensor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.
3 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between the crankshaft position 
sensor coupler and ECU 
coupler.
(gray–gray)
(black/blue–black/blue)
4 Defective crankshaft position sensor.Replace if defective.
Refer to “CHECKING THE 
CRANKSHAFT POSITION 
SENSOR” on page 7-100. 
						

							FUEL INJECTION SYSTEM
7-41
Fault code No. 13 Symptom Cylinder-#1 intake air pressure sensor: open or short cir-
cuit detected.
Diagnostic code No. 03 Cylinder-#1 intake air pressure sensor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Connections
Cylinder-#1 intake air pressure 
sensor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.Turning the 
main switch to 
“ON”.
2 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between cylinder-#1 intake air 
pressure sensor coupler and 
ECU coupler
(black/blue–black/blue)
(pink/white–pink/white)
(blue–blue)
3 Defective cylinder-#1 intake air 
pressure sensor.Execute the diagnostic mode. 
(Code No.03)
Replace if defective.
Refer to “CHECKING THE 
INTAKE AIR PRESSURE 
SENSORS” on page 7-106. 
						

							FUEL INJECTION SYSTEM
7-42
Fault code No. 14 Symptom Cylinder-#1 intake air pressure sensor: hose system mal-
function (clogged or detached hose).
Diagnostic code No. 03 Cylinder-#1 intake air pressure sensor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Cylinder-#1 intake air pressure sensor 
hoseCheck the cylinder-#1 intake air 
pressure sensor hose condition.
Repair or replace the sensor 
hose.Starting the 
engine and 
operating it at 
idle.
2 Cylinder-#1 intake air pressure sensor 
malfunction at intermediate electrical 
potential.Check and repair the 
connection.
Replace it if there is a 
malfunction.
3 Connections
Cylinder-#1 intake air pressure 
sensor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.
4 Defective cylinder-#1 intake air 
pressure sensor.Execute the diagnostic mode. 
(Code No.03)
Replace if defective.
Refer to “CHECKING THE 
INTAKE AIR PRESSURE 
SENSORS” on page 7-106. 
						

							FUEL INJECTION SYSTEM
7-43
Fault code No. 15 Symptom Throttle position sensor: open or short circuit detected.
Diagnostic code No. 01 Throttle position sensor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Installed condition of throttle position 
sensor.Check for looseness or 
pinching.
Check that the sensor is 
installed in the specified 
position.Turning the 
main switch to 
“ON”.
2 Connections
Throttle position sensor coupler
Main wire harness ECU coupler
Sub-wire harness 2 couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.
3 Open or short circuit in wire harness 
and/or sub lead.Repair or replace if there is an 
open or short circuit.
Between throttle position 
sensor coupler and ECU 
coupler
(blue–blue)
(yellow–yellow)
(back–black)
4 Throttle position sensor lead wire 
open circuit output voltage check.Check for open circuit and 
replace the throttle position 
sensor.
(black–yellow)
Open circuit 
itemOutput voltage
Ground wire 
open circuit5 V
Output wire 
open circuit0 V
Power supply 
wire open 
circuit0 V
5 Defective throttle position sensor.Execute the diagnostic mode. 
(Code No.01)
Replace if defective.
Refer to “CHECKING THE 
THROTTLE POSITION 
SENSOR” on page 7-104. 
						

							FUEL INJECTION SYSTEM
7-44
Fault code No. 17 Symptom EXUP servo motor circuit: open or short circuit detected.
Diagnostic code No. 53 EXUP servo motor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Connections
EXUP servo motor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.Turning the 
main switch to 
“ON”.
2 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between servo motor coupler 
and ECU coupler
(blue–blue)
(white/red–white/red)
(black/blue–black/blue)
3 Defective EXUP servo motor 
(potentiometer circuit).Execute the diagnostic mode. 
(Code No.53)
Replace if defective.
Refer to “CHECKING THE 
EXUP SERVO MOTOR” on 
page 7-105.
Fault code No. 18 Symptom EXUP servo motor is stuck.
Diagnostic code No. 53 EXUP servo motor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Connections
EXUP servo motor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.Turning the 
main switch to 
“ON”.
It takes 120 
seconds at the 
maximum 
before the 
original state 
returns. 2 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between the EXUP servo motor 
coupler and the ECU coupler.
(black/green–black/green)
(black/red–black/red)
3 Defective EXUP servo motor.Execute the diagnostic mode. 
(Code No.53)
Replace if defective.
Refer to “CHECKING THE 
EXUP SERVO MOTOR” on 
page 7-105.
4 Defective EXUP valve, pulley, cables. Replace if defective. 
						

							FUEL INJECTION SYSTEM
7-45
Fault code No. 19 Symptom A break or disconnection of the blue/yellow lead of the 
ECU is detected.
Diagnostic code No. 20 Sidestand switch
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Connections
Main wire harness ECU couplerExecute the diagnostic mode. 
(Code No.20)
Check the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.If the 
transmission is 
in gear, 
retracting the 
sidestand.
If the 
transmission is 
in neutral, 
reconnecting 
the wiring.
2 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between ECU and blue/yellow 
lead
3 Defective sidestand switch.Replace if defective.
Refer to “CHECKING THE 
SWITCHES” on page 7-89.
Fault code No. 22 Symptom Air temperature sensor: open or short circuit detected.
Diagnostic code No. 05 Air temperature sensor
Order Item/components and probable 
causeCheck or maintenance job Reinstatement 
method
1 Installed condition of air temperature 
sensor.Check for looseness or pinching. Turning the 
main switch to 
“ON”.
2 Connections
Air temperature sensor coupler
Main wire harness ECU couplerCheck the coupler for any pins 
that may be pulled out.
Check the locking condition of 
the coupler.
If there is a malfunction, repair it 
and connect the coupler 
securely.
3 Open or short circuit in wire harness.Repair or replace if there is an 
open or short circuit.
Between air temperature 
sensor coupler and ECU 
coupler
(brown/white–brown/white)
(black/blue–black/blue)
4 Defective air temperature sensor.Execute the diagnostic mode. 
(Code No.05)
Replace if defective.
Refer to “CHECKING THE AIR 
TEMPERATURE SENSOR” on 
page 7-107.