Geely Emgrand X7. Manual part — 190

2.12.7.22 DTC P0131 P0132 P0133 P0134

1. DTC

description:

DTC P0131

Front Oxygen Sensor Circuit Short to Low Voltage

DTC P0132

Front Oxygen Sensor Circuit Short to High Voltage

DTC P0133

Slow response of front oxygen sensor

DTC P0134

Front Oxygen sensor is open

After the vehicle started, ECM works in open-loop mode, in which ECM ignores the front oxygen
sensor signal voltage when calculating the Air-Fuel ratio. The control module provides
approximately 450mV reference voltage to the front oxygen sensor. When the engine starts
running, the front oxygen sensor will be heated and begin to generate a 0-0.1 V voltage. This
voltage fluctuates. Once ECM detects that the front oxygen sensor voltage exceeds a preset
threshold voltage, ECM immediately enters into the closed-loop mode. Control module
determines the Air-fuel ratio using the received front oxygen sensor voltage signal. If the front
oxygen sensor voltage increases to over the reference voltage (tend to 1 V), it indicates that the air
fuel mixture is too rich. If the front oxygen sensor's voltage decreased to below the reference
voltage (tend to 0 mV), the mixture is too thin.

ECM provides a signal through ECM harness connector EN01 terminal No.10 to front oxygen
sensor harness connector EN02 terminal B and an internal low reference voltage through ECM
harness connector EN01 terminal No.2 to front oxygen sensor wiring harness connector EM02
terminal No. A.

2. Conditions For Setting DTC and The Fault Location:

DTC
Code

DTC Detection Strategy

Conditions For Setting The
DTC (Control Strategy)

Fault Locations

P0131

1. Engine Running Longer

than 60s.

2. Water temperature is more

than 70 (158 ºF)

℃

3. Short circuit of front

oxygen sensor to
grounding.

4. Duration Longer Than 13s.

P0132

1. Front

Oxygen

Sensor Voltage Too
High

2. Pre-Catalytic

Oxygen Sensor
Voltage Too Low

1. Engine Running Longer

than 60s.

2. Water temperature is more

1. Sensor

Circuit

2. Sensor

3. ECM.

759

than 70 (158 ºF)

℃

3. Shortly connect front

oxygen sensor signal and
power supply.

4. Duration Longer Than 13s.

P0133

The time for the variation
of the oxygen sensor
against the oxygen
concentration in the
exhaust emissions
exceeds the upper limit.

The time for the variation
of the oxygen sensor
against the oxygen
concentration in the
exhaust emissions
exceeds the lower limit.

1. Engine Running Longer

than 60s.

2. Water temperature is more

than 70 (158 ºF)

℃

3. Engine speed range is

1,700-2,300 rpm.

4. Oxygen sensors to the

exhaust oxygen
concentration changes
responding time longer
than the system preset
threshold.

1. Sensor

Circuit

2. Sensor

3. ECM

4.Mixture is too

thick

5.Mixture Too Lean

P0134

1. Signal Circuit Open.

2.Oxygen Sensors High-
Temperature and High
Resistance.

1. Engine Running Longer

than 60s.

2. Water temperature is more

than 70 (158 ºF)

℃

3. Duration Longer Than 80s.

1. Sensor

Circuit

2. Sensor

3. ECM

3. Circuit

sketch

NL02-2057b

BAT

15

A

E

F2

1

86

87

30

85

发动机主继电器

D

EN02

C

EN02

B

EN02

A

EN02

前氧传感器

24

EN01 O

2

AHTR

47

EN01 O

2

HI

73

EN01

44

EN01

V5RTN3

MPR

ECM

Engine
main relay

Front oxygen sensor

760

4. Diagnostic

Steps:

Step 1

Connect a fault diagnosis tester.

Step 2

Start engine and turn on the fault diagnosis tester.

Step 3

(c) Keep the engine speed at 2,500 rpm for more than 2 min to warm up the engine,
until the engine coolant temperature reaches 80°C (176ºF)

Step 4

Select on the fault diagnosis tester: Engine / Read Data Flow / Group 1 Oxygen Sensor
Voltage 1 (front oxygen sensor).

Step 5

Observe the pre-catalytic oxygen sensor output voltage. The data stream
should fluctuate within 0.1-0.8 V.

Step 6

Test the oxygen sensor signal.

(a) If the voltage data is consistently lower than 0.45 V (mixture too thin), carry out the

following inspection steps:

•

Spray proper amount of propane gas into the intake.

•

Inspect whether the front oxygen sensor voltage data has a significant change, in which case
the signal voltage will increase rapidly.

(b) If the voltage data is consistently higher than 0.45V (mixture too thick), carry out the

following inspection steps:

•

Put the gear into neutral.

•

Apply hand brake.

•

Press the accelerator pedal so the engine speed suddenly increases to 4,000 rpm and then
quickly release the accelerator pedal.

•

Repeat the previous step more than 3 times.

•

Observe whether there is a significant change in the front oxygen sensor voltage data, as the
signal voltage will decrease rapidly.

Yes

Refer to 2.2.7.3 Intermittent Fault
Inspection for intermittent fault.

No

Next

Next

Next

Next

761

During the above test, the oxygen sensor signal voltage should have a significant change.

Is voltage changed significantly?

Step 6

Inspect there are no other control system DTC codes output.

(a) Connect fault diagnosis tester to the vehicle diagnostic interface.

(b) Turn ignition switch to ON position.

(c) Press the fault diagnosis tester power button.

(d) Select the following menu items: Engine/Read DTC codes.

(e) Read DTC codes.

Results

DTC Codes Shown

To Step

DTC was except for P0131、P0133、P0134 No

P0131、P0133、P0134 Yes

Step 8

Measure Pre-Sensor Signal Circuit

(a) Rotated ignition switch to OFF

position .

(b) Disconnect the front oxygen

sensor harness connector EN02.

(c) Rotated ignition switch to ON

position .

(d) Measure the voltage value

between the front oxygen sensor
wiring harness connector EN02
terminal No.B and reliable
ground.

Standard Voltage: 0.35-0.5V

(e) Connect the front oxygen sensor

harness connector EN02.

NL02-2058b

A

B

C

D

EN02 前氧传感器线束连接器

B

No

Refer to 2.12.7.14 DTC Chapter Index.

Yes

Yes

Inspect the cause for engine
air-fuel ratio too lean/too rich.
Refer to 2.12.7.4 Fault Symptom
Table.

No

EN02 front oxygen sensor harness

connector

762