Chery A1 2009 Service Manual page 191

4.
CHECK O SENSOR INPUT SIGNAL CIRCUIT FOR AN OPEN OR SHORT
2
• Check the continuity between ECM terminal and O
COMPONENT
Upstream Oxygen Sensor
• Continuity should exist.
• Check the harness for a short to power supply circuit.
Is the check result normal?
Yes >>
Go to the next step.
No >>
Repair or replace the circuit for an open or short to power in harness or connectors.
5.
CHECK O SENSOR
2
• Connect O sensor electrical connector.
2
• Connect the ECM electrical connector.
• If using the X-431, reference the data stream value.
• If not using the X-431, perform the following:
− Start engine and warm it up to normal operating temperature 90°C.
− Turn ignition switch off.
− Start engine and maintain the engine speed between 3,500 RPM and 4,000 RPM for at least 1 minute.
− Let engine idle for 1 minute.
• Connect digital multimeter probes between ECM terminal 4 and ground, harness side.
CHECK
CHECK CONTENT
ITEM
• Warm-up
condition
• Become
lean while
decelerate
• Warm-up
condition
Oxygen
• Become
sensor
rich while
accelerate
• Warm-up
condition
• Check with
O sensor
2
signal
Is the check result normal?
Yes >>
Go to the next step.
No >>
Replace O sensor.
2
84
03–
DIAGNOSIS & TESTING
O SENSOR SIGNAL CIRCUIT
2
ECM
O SENSOR OUTPUT SIGNAL
2
NORMAL
VALUE
Decelerate
from
Below 100
approximately
mV
4,000 RPM
suddenly
Approximately
Accelerate
600 - 900
suddenly
mV
100 - 900
Idle
mV
Approximately
Approximately
600 - 900
2500 RPM
mV
sensor terminal as follows:
2
Chery Automobile Co., Ltd.
TERMINAL
18
4