Workshop Manual

11.5 Rear Oxygen Sensor Failure
Failure codes: P0136, 0137, 0138, 0036, 0037, 0038, 0054
No. Operating steps Result Follow up steps
1 Put the ignition switch to “ON”. Next step
Yes Next step 2 Pull off the oxygen sensor connector of harness.
Check the voltage between pin 1# (+) and 2# (-)
with multimeter and detect if it is around 12V.
No 4
Yes Replace ECU 3 Use a multimeter to check if the resistance value
between 1# and 2# pins of the oxygen sensor is
between 2Ω and 5Ω at 23.℃
No Replace the sensor
Yes Next step 4 Check if heating circuit of the oxygen sensor is
normal.
No Check the circuit
Yes Repair or replace
harness
5 Check if it is short circuit or break circuit between
pin 2# of oxygen sensor and main relay 87# pin
and between the sensor connector 1# pin and ECU
1# pin with multimeter.
No Next step
6 Connect the oxygen sensor connector of harness
and use neutral. Start the engine and leave it at
idle speed until its coolant temperature reaches to
the normal value.
Next step
Next step 7 Validate if the three-way catalytic converter works
normally.
Yes
No
Replace the
three-way catalytic
converter
Yes Next step 8 Pull out the oxygen sensor joint on harness.
Rapidly apply the accelerator pedal for several
times, and then use a multimeter to check if a
output voltage between 0.1V and 0.9V is present
between 3# (+) and 4# (-) pins of the sensor (after
the engine warms up).
No Replace the sensor
Yes Repair or replace
harness
9 Connect the adaptor between ECU and harness.
Check if it is short circuit or break circuit between
the pin 36# and pin 55# of ECU and the sensor
connector 3# and 4# pins respectively with
multimeter.
No Replace ECU
10 Connect the oxygen sensor connector of harness
and use neutral. Start the engine and leave it at
idle speed until its coolant temperature reaches to
the normal value.
Next step
11 Connect special diagnostic tester for Chery to read Yes Next step