SEF463R
SEF288D
Component Description
NHEC0116
The heated oxygen sensor 1 (front) is placed into the front tube. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 (front) has a closed-end
tube made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions.
The heated oxygen sensor 1 (front) signal is sent to the ECM. The
ECM adjusts the injection pulse duration to achieve the ideal air-
fuel ratio. The ideal air-fuel ratio occurs near the radical change
from 1V to 0V.
CONSULT-II Reference Value in Data Monitor
Mode
NHEC0117
Specification data are reference values.
MONITOR ITEM
CONDITION
SPECIFICATION
HO2S1 (B1)
HO2S1 (B2)
I
Engine: After warming up
Maintaining engine speed at 2,000
rpm
0 - 0.3V
+,
Approx. 0.6 - 1.0V
HO2S1 MNTR
(B1)
HO2S1 MNTR
(B2)
LEAN
+,
RICH
Changes more than 5 times during
10 seconds.
SEF301U
On Board Diagnosis Logic
NHEC0119
To judge the malfunction, the diagnosis checks that the heated
oxygen sensor 1 (front) output is not inordinately high.
Malfunction is detected when an excessively high voltage from the
sensor is sent to ECM.
GI
MA
EM
LC
FE
AT
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0134 (BANK 1), P0154 (BANK 2) HO2S1 (FRONT) (HIGH VOLTAGE)
Component Description
EC-231