Fail-Safe Function - Suzuki VZR1800 2007 Service Manual

FAIL-SAFE FUNCTION

FI system is provided with fail-safe function to allow the engine to start and the motorcycle to run in a mini-
mum performance necessary even under malfunction condition.
ITEM
IAP sensor
TP sensor
ECT sensor
IAT sensor
Ignition signal
Injection signal
Secondary throttle valve
actuator
STP sensor
Gear position signal
Heated oxygen sensor
(E-02, 19, 24)
PAIR control solenoid valve
EXCV actuator
ISC valve
The engine can start and can run even if the above signal is not received from each sensor. But, the engine
running condition is not complete, providing only emergency help (by fail-safe circuit). In this case, it is nec-
essary to bring the motorcycle to the workshop for complete repair.
When two ignition signals or two injector signals are not received by ECM, the fail-safe circuit can not work
and ignition or injection is stopped.
FAIL-SAFE MODE
Intake air pressure is fixed to 760
mmHg.
The throttle opening is fixed to full open
position.
Engine coolant temperature value is
fixed to 80 °C (176 °F).
Intake air temperature value is fixed to
40 °C (104 °F).
#1.1 or #1.2 Ignition-off
#2.1 or #2.2 Ignition-off
#1 Fuel-cut
#2 Fuel-cut
Secondary throttle valve is fixed to full
close position. When motor disconnec-
tion or lock occurs, power from ECM is
shut off.
Secondary throttle valve is fixed to full
close position.
Gear position signal is fixed to 5th
gear.
Fuel-air compensation ratio is fixed to
normal condition.
ECM stops controlling PAIR control
solenoid valve.
EXCV actuator is fixed to full open
position. When motor disconnection or
lock occurs, power from ECM is shut
off.
When motor disconnection or lock
occurs, power from ECM is shut off.
FI SYSTEM DIAGNOSIS
STARTING RUNNING
ABILITY ABILITY
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
#1 cylinder can run.
"YES" "YES"
#2 cylinder can run.
"YES" "YES"
#2 cylinder can run.
"YES" "YES"
#1 cylinder can run.
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
"YES" "YES"
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