Substitute Characteristics Operation Control; Fail-Safe Action - Yamaha XV1700PCRC Service Manual

SUBSTITUTE CHARACTERISTICS OPERATION CONTROL (FAIL-SAFE ACTION)
If the ECU detects an abnormal signal from a sensor while the motorcycle is being driven, the ECU
illuminates the engine trouble warning light and provides the engine with substitute characteristic
operation instructions that are appropriate for the type of the malfunction.
When an abnormal signal is received from a sensor, the ECU processes the specified values that
are programmed for every sensor, in order to provide the engine with substitute characteristics
operation instructions that enable the engine to continue to operate (or to stop its operation,
depending on circumstances).
The ECU takes fail-safe actions in two ways: one in which the sensor output is set to a prescribed
value, and the other in which the ECU directly operates an actuator. Details on the fail-safe actions
are given in the table below.
Table of substitute characteristic operation control by self-diagnostic fault code
Code No. Item
Cylinder identification
11 sensor
Crankshaft position sen-
12
sor
13 Intake air pressure sensor
14 (open or short circuit)
25 (pipe system)
26
Throttle position sensor
15
(open or short circuit)
16
(stuck)
Sidestand switch
19 (open circuit in wire to
ECU)
Atmospheric pressure
20 sensor or intake air pres-
sure sensor
Intake temperature sen-
22
sor
Atmospheric pressure
23
sensor
27 Oil temperature sensor
Engine temperature sen-
28
sor
Decompression thermo-
29
stat
37 Linear control valve
38 Decompression solenoid
Lean angle cut-off switch
30
(latch up detected)
41
(open or short circuit)
Speed sensor, neutral
42
switch
Fuel system voltage
43
(monitor voltage)
ECU internal malfunction
50
(memory check error)
FUEL INJECTION SYSTEM

Fail-safe action

• Continues to operate the engine based on the
results of the cylinder identification that existed up
to that point.
• Stops the engine (by stopping the injection and
ignition).
• Fixes the intake air pressure to 760 mmHg.
• Fixes the throttle position sensor to fully open.
-- (No start)
• Fixes the atmospheric correction value to 0 mmHg.
• Fixes the intake temperature to 15 °C (59 °F).
• Fixes the atmospheric pressure to 760 mmHg.
• Fixes the oil temperature to 80 °C (176 °F).
• Fixes the engine temperature to 140 °C (284 °F).
• Electricity is not circulated to the decompression
solenoid and the thermostat is not operated.
--
--
• Turns OFF the fuel injection system relay of the fuel
system.
• Fixes the gear to the top gear.
• Fixes the battery voltage to 12 V.
--
6 - 8
FI
Able/unable to Able/unable to
start drive
Able Able
Unable Unable
Able Able
Able Able
Unable Unable
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Able Able
Unable Unable
Able Able
Able Able
Unable Unable