HYOSUNG 2010 ST7 Service Manual page 135

▣ ▣ INSPECTION
1) Remove the front seat and right side cover.
2) Turn the ignition switch "OFF" position.
3) Check the Oxygen sensor coupler for loose or
poor contacts.
Is OK?
● B or GR (NO.1 O ₂ ₂ S) / R or GR
(NO.2 O ₂ ₂ S) wire open or shorted
to ground, or poor
(NO.1 O ₂ ₂ S) /
(NO.2 O ₂ ₂ S) connection of ECU
coupler. (Sensor side)
● YL or W (NO.1 O ₂ ₂ S heater) / YL
or L (NO.2 O ₂ ₂ S heater) wire
open or shorted to ground, or
poor
YES /
G4
connection of ECU coupler.
YL coupler open or shorted to
the wiring harness.
(Heater side)
● If wire and connection are OK,
intermittent trouble or faulty
ECU.
● Recheck each terminal and wire
harness for open circuit and
poor connection.
Replace the Oxygen sensor with a
NO
new one.
or
B17 B10
or
G5 B10
(NO.1 O ₂ ₂ S heater)
B7
(NO.2 O ₂ ₂ S heater)
EI SYSTEM DIAGNOSIS 4-28
Gray
ECU Coupler
Sensor side Heater side
GR B W
NO.1 O ₂ ₂ S
Sensor side Heater side
GR R L
NO.2 O ₂ ₂ S
Black
YL
YL