Suzuki GSX-R750 Service Manual page 181

Step
2 1) Connect the ECM coupler and HO2 sensor coupler.
2) Warm up the engine enough.
3) Insert the needle pointed probes to the lead wire coupler.
4) Measure the HO2 sensor output voltage between the W/
G wire and B/Br wire, in idling condition.
Special tool
(A): 09900–25008 (Multi-circuit tester set)
(B): 09900–25009 (Needle pointed probe set)
Tester knob indication
Voltage ( )
HO2 sensor output voltage at idle speed
0.4 V and less
((+) terminal: W/G – (–) terminal: B/Br)
5) If OK, then remove the air cleaner box and pinch the
PAIR hose (1) with a proper hose clamp.
6) Measure the HO2 sensor output voltage while holding
the engine speed at 5 000 r/min.
HO2 sensor output voltage at 5 000 r/min
0.6 V and more
((+) terminal: W/G – (–) terminal: B/Br)
Is the voltage OK?
Action
(A)
(B)
1
Engine General Information and Diagnosis:
Yes
• W/G or B/Br wire
open or shorted to
the power source, or
poor "34" or "35"
connection.
• If wire and
connection are OK,
intermittent trouble or
faulty ECM.
• Recheck each
terminal and wire
harness for open
circuit and poor
connection.
• Replace the ECM
with a known good
one, and inspection it
again. Refer to "ECM
Removal and
Installation in Section
1C (Page 1C-1)".
I837H1110146-02
I837H1110147-01
1A-109
No
Replace the HO2
sensor with a new one.
Refer to "HO2 Sensor
Removal and
Installation in Section
1C (Page 1C-9)".