Yes

Step 8

Diagnostic completed.

5. Repair Instructions:

Replace the Pre-Catalytic oxygen sensor. Refer to 

2.4.7.2

 

Pre-Catalytic Oxygen Sensor Replacement

.

2.2.7.16 DTC P0036 P0037 P0038 P0054

1. DTC Descriptor:

DTC

P0036

Post-Catalytic Oxygen Sensor Heating Control Circuit Open

DTC

P0037

Post-Catalytic Oxygen Sensor Heating Control Circuit Short to Ground

DTC

P0038

Post-Catalytic Oxygen Sensor Heating Control Circuit Short to Power Supply

DTC

P0054

Post-Catalytic Oxygen Sensor Heating Resistance Unreasonable

The Post-Catalytic heated oxygen sensor (HO

2

S) is used for monitoring three-way catalytic converter working status. The sensor

compares the oxygen content in ambient air with the oxygen content in exhaust flow. Each heated oxygen sensor has an internal
heating element for sensor heating. ECM controls the heated oxygen sensor heating control circuit. This makes the system enter
into the closed-loop control mode earlier, so that ECM can calculate Air-Fuel ratio earlier. ECM commands heater control module
switched on or off, so that heated oxygen sensor works within the specified working temperature range. Engine control module
detects the temperature by Measure the heater current.

The Post-Catalytic heated oxygen sensor heating coil voltage is provided by The Main Relay, which is controlled by ECM. When
the ignition switch is turned to "ON" position, the Post-Catalytic oxygen sensor harness connector EN03 terminal No.1 voltage is
provided by the battery. ECM controls heater working time through ECM harness connector EN01 terminal No.4.

2. Conditions For Setting DTC and The Fault Location:

DTC Code

DTC Detection

Strategy

Conditions For Setting The DTC (Control Strategy)

Fault Locations

P0036
P0037
P0038

Hardware Circuit
Checks

1. Circuit Open

2. Circuit Short to Ground

3. Circuit Short to Power Supply

1. Sensor Circuit

2. Sensor

3. ECM

P0054

The current resistance
is greater than the set
value.

1. The oxygen sensor current internal resistance is greater

than 1700 Ω.

2. The current exhaust gas temperature is between 200°C

(392 ºF) and 550°C (1,022 ºF).

Engine

Control System JL4G18-D

2-83

3. Schematic:

12

14

Main Relay

From Battery

Engine 

Control 

Module

From Pre-catalytic Oxygen Sensor

Post-catalytic Oxygen Sensor

FE02-5012b

4. Diagnostic Steps:

Note

Before carrying out this diagnosis step, observe the data list on scan tool and analyze the accuracy of the data, as
these will help with quick diagnosis.

Step 1

Initial Inspection

Check the existence of following factors that will affect the oxygen
sensor working status:

(a)

Exhaust system leaks or blockage.

(b)

Water entering into heated oxygen sensor connector.

(c)

After engine worked in high temperatures, check whether
exhaust pipes are too hot.

Next

Step 2

Check the Post-Catalytic oxygen sensor heater resistance.

2-84

Control System JL4G18-D

Engine

2

3

4

1

Post-catalytic Oxygen Sensor 

FE02-5013b

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the post-catalytic oxygen sensor wiring harness
connector.

(c)

Measure the Post-Catalytic oxygen sensor heater resistance.

Standard Resistance: Between connector No.1 and No.2, 9 Ω
(68 ºF) at 20°C

(d)

Connect the post-catalytic oxygen sensor wiring harness
connector.

Is the resistance the specified value?

No

Replace oxygen sensor. Refer to 

2.4.7.1

 

Post-

Catalytic Oxygen Sensor Replacement

Yes

Step 3

Check the terminal No.2 to ground voltage.

FE02-5014b

1

2

3

4

Post-catalytic Oxygen Sensor 

Harness Connector EN03

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the post-catalytic oxygen sensor wiring harness
connector.

(c)

Turn the ignition switch to "ON" position.

(d)

Measure the Post-Catalytic oxygen sensor harness
connector EN03 terminal No.1 to ground voltage.

Standard Voltage: 11-14 V

(e)

Connect the post-catalytic oxygen sensor wiring harness
connector EN03.

Is voltage the specified values?

No

The Post-Catalytic oxygen sensor heater
power supply circuit malfunction.

Yes

Step 4

Check the Post-Catalytic oxygen sensor heater control terminal continuity.

Engine

Control System JL4G18-D

2-85

FE02-5015b

1

3

5

7

8

6

4

2

9

10

11

12

13

23

24

25

26

27

28

29

30

37

51

52

53

54

55

56

57

58

59

60

61

62

63

64

38

39

40

41

42

43

44

45

46

47

48

49

50

31

32

33

34

35

36

14

15

16

17

18

19

20

21

22

1

2

3

4

Post-catalytic Oxygen Sensor Harness 

Connector EN03

ECM Harness Connector EN01

(a)

Turn the ignition switch to "OFF" position.

(b)

Disconnect the post-catalytic oxygen sensor wiring harness
connector EN03.

(c)

Disconnect ECM harness connector EN01.

(d)

Measure the continuity between the post-catalytic oxygen
sensor wiring harness connector EN03 terminal No.2 and
ECM harness connector EN01 terminal No.4.

Standard Resistance: Less than 1 Ω

(e)

Connect ECM harness connector EN01.

(f)

Connect the post-catalytic oxygen sensor wiring harness
connector EN03.

Is resistance the specified value?

No

ECM control circuit malfunction

Yes

Step 5

Check ECM working circuit.

(a)

Check whether ECM power supply circuit is normal.

(b)

Check whether ECM ground circuit is normal.

No

Repair the faulty part.

Yes

Step 6

Replace ECM. Refer to 

2.2.8.8

 

Engine Control Module Replacement

.

Next

Step 7

Use scan tool to confirm whether the DTC code is stored again.

(a)

Connect scan tool to the datalink connector.

(b)

Turn the ignition switch to "ON" position.

(c)

Clear DTC code.

(d)

Start and run the engine at idle speed to warm up the engine
for at least 5 min.

(e)

Road test the vehicle for at least 5 min.

(f)

Read control system DTC code again to confirm that the
system has no DTC code.

No

Intermittent Fault. Refer to 

2.2.7.3

 

Intermittent

Fault Check

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Control System JL4G18-D

Engine