Ecu Self-Diagnostic Function; Self-Diagnostic Function Table - Yamaha Apex RX10PA 2011 Supplementary Service Manual

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
engine under substitute characteristics and the warning light and self-diagnostic warning indicator
on the upper LCD flash to alert the rider that a malfunction has occurred in the system. Once a mal-
function has been detected, a fault code is stored in the memory of the ECU.
• If a malfunction is detected in the system by the self-diagnostic function, the ECU provides an
appropriate substitute characteristic operation, and the warning light and self-diagnostic warning
indicator on the upper LCD flash to alert the rider of the detected malfunction.
• The lowest fault code number appears on the lower LCD. Once a fault code has been displayed, it
remains stored in the memory of the ECU until it is deleted.

SELF-DIAGNOSTIC FUNCTION TABLE

If the ECU detects an abnormal signal from a sensor while the snowmobile is being driven, the
warning light and self-diagnostic warning indicator on the upper LCD flash to alert the rider that a
malfunction has occurred and the ECU 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.
Self-Diagnostic-Function table
Fault code
Item
No.
Cylinder identification sensor
11
Crankshaft position sensor
12
Intake air pressure sensor (cylin-
13 ders #1, #2, #3, and #4) (open or
short circuit)
Intake air pressure sensor (cylin-
ders #1, #2, #3, and #4) (hose
line)
14
Throttle position sensor (open or
15
short circuit)
Throttle position sensor (stuck)
16
EXUP servo motor circuit (open or
17
short circuit)
EXUP servo motor (stuck)
18
Intake air pressure or atmospheric
pressure
20
Coolant temperature
21
(open or short circuit)
Intake air temperature sensor
22
(open or short circuit)
FUEL INJECTION SYSTEM
Symptom
No normal signals are received from
the cylinder identification sensor.
No normal signals are received from
the crankshaft position sensor.
No normal signals are received from
the intake air pressure sensor.
Intake air pressure sensor: hose sys-
tem malfunction (clogged or detached
hose).
Intake air system failure (the pressure
is not supplied to the intake air pres-
sure sensor in a stable condition.)
No normal signals are received from
the throttle position sensor.
Signal from throttle position sensor will
not change.
No normal signals are received from
the EXUP servo motor circuit.
Signal from EXUP servo motor position
will not change.
When turning the main switch to "ON",
the voltage value shows great differ-
ence between the intake air pressure
sensor and atmospheric pressure sen-
sor.
sensor No normal signals are received from
the coolant temperature sensor.
No normal signals are received from
the intake air temperature sensor.
91
FI
Able/unable Able/unable
to start to drive
Able
Unable (under certain
conditions)
Unable Unable
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able