4-15
3
）
Maintenance of oxygen sensor
4
）
Maintenance of cylinder temperature and air temperature sensor
3. Fault code 24----oxygen sensor
The figure on the right is the electric diagram
Connect No.1 stitch to ECU No. 24 stitch
Connect No.2 stitch to ECU No. 13 stitch
Connect No.3 stitch to power output (12V) of
fuel pump relay
Connect No.4 stitch to vehicle ground wire
(green)
Maintenance steps
S/N
Steps
Result
Subsequent steps
1
Open the key switch, run the fuel pump for 3
seconds by listening (by touching is also ok).
Start the engine.
Next step
2
Extract the sensor plug on the cable. Check
with multimeter to see if the voltage between
No.3 and No.4 stitches is 12V.
YES
Next step
NO
4
3
Check with multimeter to see if the
resistance value between No.3 and No.4
stitches is about 6~25
Ω
.
YES
Replace the ECU
NO
Next step
4
Check with multimeter to see if there’s short
circuit or broken circuit between No.3 stitch
and power output (12V) of fuel pump relay;
and between No.3 stitch and vehicle ground
wire (green).
YES
Repair or replace
the cable
NO
Next step
5
Insert the oxygen sensor plug on the cable.
Set it to neutral gear. Start the engine and
make it in idle speed till the cylinder
temperature is about 80
℃
.
Next step
6
Extract the sensor plug on the cable. Check
with multimeter to see if there’s voltage
output (0.1~0.9V) between No.1 and No.2
stitches.
YES
Next step
NO
Replace the sensor
7
Check with multimeter to see if there’s short
circuit or broken circuit between ECU
No.13, 24 and sensor No.1, 2 stitches.
YES
Repair or replace
the cable
NO
Replace the ECU
Maintenance steps
S/N
Steps
Result
Subsequent steps
1
Open the key switch, run the fuel pump for 3 seconds by listening (by
touching is also ok). Start the engine.
Next step
2
Check with multimeter to see if the resistance value between No.1 and
No.2 stitches corresponds with the temperature (refer to the related part
in this service manual).
YES
Replace the ECU
NO
Next step
3
Check with multimeter to see if there’s short circuit or broken circuit
between ECU No.11, 13, 23 stitches and their corresponding stitches on
the sensor.
YES
Repair or replace the cable
NO
Replace the ECU
