Yamaha YZF-R15, Service Manual

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FUEL INJECTION SYSTEM FUEL INJECTION SYSTEM
ECU 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 the ECU.
• To inform the rider that the fuel injection system is not functioning, the engine trouble warning light
flashes when the start switch is being pushed to start the engine.
• If a malfunction is detected in the system by the self-diagnostic function, the ECU provides an appro-
priate substitute characteristic operation, and alerts the rider of the detected malfunction by illuminat-
ing the engine trouble warning light.
• After the engine has been stopped, the fault code number appears on the engine trouble warning
light (or displayed on the FI diagnostic tool). It remains stored in the memory of the ECU until it is
deleted.
Engine trouble warning light fault code indication
Digit of 10: Cycles of 1 sec. ON and 1.5 sec. OFF.
Digit of 1: Cycles of 0.5 sec. ON and 0.5 sec. OFF.
Example: 42
1. Engine trouble warning light
a. Light ON
b. Light OFF
c. 1 sec.
d. 1.5 sec.
e. 0.5 sec.
f.
3 sec.
1
Engine trouble warning light indication and fuel injection system operation
* The warning light flashes when any one of the conditions listed below is present and the start switch
is pushed:
Checking the engine trouble warning light bulb
The engine trouble warning light comes on for 3 seconds after the main switch has been turned to“ON”.
If the warning light does not come on under these conditions, the communication wire disconnection or
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 instructions that
enable the engine to continue to operate or stop operating, depending on the conditions.
Warning light indica-
tion
ECU operation
Fuel injection opera-
tion
Vehicle operation
Flashing*
Warning provided
when unable to start
engine
Operation stopped Cannot be operated
Remains on Malfunction detected
Operated with substi-
tute characteristics in
accordance with the
description of the mal-
function
Can or cannot be oper-
ated depending on the
fault code
30:
Lean angle sensor
41:
Lean angle sensor
(open or short circuit)
33: Faulty ignition 50:
ECU internal malfunction
(memory check error)
39:
Fuel injector
(open or short circuit)
a. Main switch “OFF”
b. Main switch “ON”
c. Engine trouble warning light off d. Engine trouble warning light on for 3 seconds
Engine trouble warning light indication and fuel injection system operation
* The warning light flashes when any one of the conditions listed below is present and the start switch
is pushed:
Checking the engine trouble warning light bulb
“ ”.
Warning light indica-
tion
ECU operation
Fuel injection opera-
tion
Vehicle operation
Flashing*
Warning provided
when unable to start
engine
Operation stopped Cannot be operated
Remains on Malfunction detected
Operated with substi-
tute characteristics in
accordance with the
description of the mal-
function
Can or cannot be oper-
ated depending on the
fault code
30: 41:
Lean angle sensor
(open or short circuit)
33: Faulty ignition 50:
ECU internal malfunction
(memory check error)
39:
Fuel injector
(open or short circuit)
a. Main switch “OFF”
b. Main switch “ON”
c. Engine trouble warning light off d. Engine trouble warning light on for 3 seconds
(when starter switch is
pushed)
(rollover detected)
the warning light LEDs may be defective.
NOTE :
Engine unable to start under following conditions.
Engine trouble warning light flashes when the start switch is pushed.