Yamaha Mt 01 T 2005 Manual

FUEL INJECTION SYSTEM
7-26
3. Main switch
4. Battery
5. Fuel injection system fuse
8. Main fuse
10.ECU fuse
15.Fuel pump relay
16.Neutral switch
17.Fuel pump
19.Sidestand switch
20.Crankshaft position sensor
21.Throttle position sensor
22.Cylinder-#1 intake air pressure sensor
23.Cylinder-#2 intake air pressure sensor
24.Lean angle cut-off switch
25.Speed sensor
26.Muffler cooling fan temperature sensor
27.Air temperature sensor
28.Engine temperature sensor
29.ECU (electronic control unit)
30.ISC (idle...

FUEL INJECTION SYSTEM
7-27
EAS27350ECU SELF-DIAGNOSTIC FUNCTION
The ECU is equipped with a self-diagnostic function in order to ensure that the fuel injection system is 
operating normally. If this function detects a malfunction in the system, it immediately operates the en-
gine under substitute characteristics and illuminates the engine trouble warning light to alert the rider 
that a malfunction has occurred in the system. Once a malfunction has been detected, a fault code is 
stored in the memory of...

FUEL INJECTION SYSTEM
7-28
EAS27380
SELF-DIAGNOSTIC FUNCTION TABLE
If the ECU detects an abnormal signal from a sensor while the vehicle is being driven, the ECU illumi-
nates the engine trouble warning light and provides the engine with alternate operating instructions that 
are appropriate for the type of malfunction.
When an abnormal signal is received from a sensor, the ECU processes the specified values that are 
programmed for each sensor in order to provide the engine with alternate operating...

FUEL INJECTION SYSTEM
7-29
24O2 sensorNo normal signal is received from 
the O2 sensor.Able Able
25Cylinder-#2 intake air 
pressure sensor
(open or short circuit)Cylinder-#2 intake air pressure 
sensor: open or short circuit 
detected.Able Able
26Cylinder-#2 intake air 
pressure sensor
(hose system)Cylinder-#2 intake air pressure 
sensor: hose system malfunction 
(clogged or detached hose).Able Able
28Engine temperature 
sensor
(open or short circuit)Engine temperature sensor: open 
or short circuit...

FUEL INJECTION SYSTEM
7-30
Communication error with the meter42Speed sensorNo normal signals are received 
from the speed sensor.
Able Able
Neutral switchOpen or short circuit is detected in 
the neutral switch.
43Fuel system voltage
(monitoring voltage)The ECU is unable to monitor the 
battery voltage
(an open or short circuit in the line 
to the ECU).Able Able
44Error in writing the 
amount of CO 
adjustment on 
EEPROMError is detected while reading or 
writing on EEPROM (CO 
adjustment value).Able...

FUEL INJECTION SYSTEM
7-31
EAS27400TROUBLESHOOTING METHOD
The engine operation is not normal and the 
engine trouble warning light comes on.
1. Check:
Fault code number



 





 
 








 
 



 
 



 



a. Check the fault code number displayed on 
the meter.
b. Identify the faulty system with the fault code. 
Refer to “Self-Diagnostic Function table”.
c. Identify the probable cause of the malfunc-
tion. Refer to “Diagnostic code table”.
        
2. Check and repair...

FUEL INJECTION SYSTEM
7-32
NOTE:
All displays on the meter disappear except the clock and odometer/trip meter/fuel reserve trip meter 
displays.
“dIAG” appears on the odometer/trip meter/fuel reserve trip meter LCD.
4. Press the “SELECT” button to select the diagnostic mode “dIAG”.
5. After selecting “dIAG”, simultaneously press the “SELECT” and “RESET” buttons for 2 seconds or 
more to activate the diagnostic mode. The diagnostic code number “d01” appears on the clock LCD.
6. Set the engine stop...

FUEL INJECTION SYSTEM
7-33
14Cylinder-#1 intake air 
pressure sensor: hose 
system malfunction 
(clogged or detached 
hose).Cylinder-#1 intake air pressure sensor hose 
is detached, clogged, kinked, or pinched.
Malfunction in ECU.03
15Throttle position sensor: 
open or short circuit 
detected.Open or short circuit in wire sub lead.
Open or short circuit in wire harness.
Defective throttle position sensor.
Malfunction in ECU.
Improperly installed throttle position sensor.01
17EXUP servo motor...

FUEL INJECTION SYSTEM
7-34
33Malfunction detected in the 
primary wire of the 
cylinder-#1 left or right 
ignition coil.Open or short circuit in wire sub lead.
Open or short circuit in wire harness.
Malfunction in cylinder-#1 left or right 
ignition coil.
Malfunction in ECU.
Malfunction in a component of ignition cut-
off circuit system.30
32
34Malfunction detected in the 
primary wire of the 
cylinder-#2 left ignition coil.Open or short circuit in wire harness.
Malfunction in cylinder-#2 left...

FUEL INJECTION SYSTEM
7-35
42No normal signals are 
received from the speed 
sensor.
Open circuit is detected in 
the neutral switch.Open circuit in wire harness.
Defective speed sensor.
Malfunction in vehicle speed sensor 
detected.
Defective neutral switch.
Malfunction in the engine side of the neutral 
switch.
Malfunction in ECU.07
21
43The ECU is unable to 
monitor the battery voltage 
(an open or short circuit in 
the line to the ECU).Open or short circuit in wire harness.
Malfunction in...