Self-Diagnosis Function - Suzuki GSX-R750 Service Manual

Self-Diagnosis Function

The self-diagnosis function is incorporated in the ECM. The function has two modes, "User mode" and "Dealer mode".
The user can only be notified by the LCD (DISPLAY) panel and LED (FI indicator light). To check the function of the
individual FI system devices, the dealer mode is provided. In this check, the special tool is necessary to read the code
of the malfunction items.
User Mode
Malfunction
"NO"
Engine can start
"YES"
Engine can not start
*1
When one of the signals is not received by ECM, the fail-safe circuit works and injection is not stopped. In this case,
"FI" and coolant temperature are indicated in the LCD panel and motorcycle can run.
*2
The injection signal is stopped, when the camshaft position sensor signal, crankshaft position sensor signal, tip-over
sensor signal, #1, #2, #3 and #4 ignition signals, #1, #2, #3 and #4 injector signals, fuel pump relay signal or ignition
switch signal is not sent to ECM. In this case, "FI" is indicated in the LCD panel. Motorcycle does not run.
"CHEC":
The LCD panel indicates "CHEC" when no communication signal from the ECM is received for 5 seconds.
For Example:
The ignition switch is turned ON, and the engine stop switch is turned OFF. In this case, the speedometer does not
receive any signal from ECM, and the panel indicates "CHEC". If CHEC is indicated, the LCD does not indicate the
trouble code. It is necessary to check the wiring harness between ECM and speedometer couplers.The possible
cause of this indication is as follows:
Engine stop switch is in OFF position. Side-stand/ignition inter-lock system is not working. Ignition fuse is burnt.
"Sd":
The LCD panel indicates "Sd" when the steering damper solenoid malfunction, battery abnormal voltage and speed
sensor malfunction occurred.
NOTE
Until starting the engine, the FI indicator light turns ON. The FI indicator light is also turned ON when
engine temperature is high or oil pressure is low.
LCD (DISPLAY)
INDICATION "A"
Coolant temperature
Coolant temperature and "FI"
letters
*1
"FI" letter
*2
Engine General Information and Diagnosis:
FI INDICATOR LIGHT
INDICATION "B"
—
FI indicator light turns ON.
FI indicator light turns ON
and blinks.
"A"
"B"
1A-3
B838H21101002
INDICATION MODE
—
Each 2 sec. Coolant
temperature or "FI" is
indicated.
"FI" is indicated
continuously.
I837H1110001-01