Chery Tiggo 5 (T21). Service manual — part 331

31–

28

31

DTC

B2120

AC in Car Temperature Sensor Short to Ground or Open
Circuit (Left Side)

DTC

B2121

AC in Car Temperature Sensor Short to Ground or Open
Circuit (Right Side)

ET21310090

HVAC
CONTROL
PANEL

K-012

BATTERY

RF10

7.5A

RF21

10A

IGNITION SWITCH
ON OR START

10

21

1

2

3

4

5

6

7

8

9 10 11 12

13

85

85

87

87 30

87 30

30

86

86

85

86

14 15 16 17 18 19 20 21 22 23 24

25

27

26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

W

K-012

22 21 20

18

19

17 16 15

13

14

12 11 10

8

9

7

6

5

3

4

2

1

B

I-039

B

I-007

2

WB

BR

4

21

WV

19

Y

INSTRUMENT
PANEL FUSE
AND RELAY
BOX

I-007

I-039

K-007

4

B

BrW

8

I-039

K-007

I-037

W

K-007

1

2

3

4

5

6

8

9

10 11

13 14

15 16

18

17

21

20

22

7

12

19

BrY

34

22

2

1

BlW

WY

35

2

1

BlW

2

1

2

1

W

K-001

W

K-011

LEFT ROOM
TEMPERATURE
SENSOR

K-011

RIGHT ROOM
TEMPERATURE
SENSOR

K-001

31–

29

31

Diagnosis Procedure

Use the circuit diagram as a guide to perform the following procedures:
a. Turn ignition switch to LOCK.
b. Disconnect the negative battery cable.
c. Disconnect the HVAC control panel assembly connector K-012.
d. Disconnect the left room temperature sensor connector K-011 and right room temperature sensor

connector K-001.

e. Check if wire harnesses are worn, pierced, pinched or partially broken.
f. Look for broken, bent, protruded or corroded terminals.
g. Check if related connector pins are in good condition.

a. Remove the room temperature sensor.
b. Install the new room temperature sensor to vehicle.
c. Use X-431 3G diagnostic tester to check if DTCs are still output.

DTC Code

DTC Definition

DTC Detection

Condition

Possible Cause

B2120

AC in Car Temperature
Sensor Short to
Ground or Open Circuit
(Left Side)

Ignition switch ON

 Room temperature sensor
 Wire harness and connector
 HVAC control panel

B2121

AC in Car Temperature
Sensor Short to
Ground or Open Circuit
(Right Side)

CAUTION

 When performing electrical equipment diagnosis and test, always refer to the circuit diagram for related

circuit and component information.

1

Check wire harness and connector

Repair or replace A/C wire harness and
connector

NG

2

Check room temperature sensor

OK

Replace room temperature sensor

NO

YES

31–

30

31

a. Turn ignition switch to LOCK.
b. Disconnect the negative battery cable.
c. Disconnect the HVAC control panel assembly connector

K-012.

d. Disconnect the left room temperature sensor connector

K-011 and right room temperature sensor connector



K-001.

e. Using a digital multimeter, check for continuity between

terminals of connector K-012 and connector K-011 to
check if there is an open in left room temperature sensor
according to the table below.
Standard Condition

f. Using a digital multimeter, check for continuity between

terminals of connector K-012 and connector K-001 to
check if there is an open in right room temperature
sensor according to the table below.
Standard Condition

3

Check wire harness and connector (HVAC control panel assembly - room temperature
sensor)

RT21311040

-

+

K-012

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

K-011

2

1

Multimeter

Connection

Condition

Specified

Condition

K-012 (22) -

K-011 (2)

Always

Continuity

K-012 (34) -

K-011 (1)

Always

Continuity

RT21311050

-

+

K-012

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

K-001

2

1

Multimeter

Connection

Condition

Specified

Condition

K-012 (22) -

K-001 (2)

Always

Continuity

K-012 (35) -

K-001 (1)

Always

Continuity

Repair or replace A/C wire harness and
connector

NG

OK

31–

31

31

a. Turn ignition switch to LOCK.
b. Disconnect the negative battery cable.
c. Disconnect the HVAC control panel assembly connector

K-012.

d. Using a digital multimeter, check for continuity between

connector K-012 and body ground to check if system is
short to ground according to the table below.
Standard Condition

a. Reconnect all disconnected connectors securely.
b. Connect the negative battery cable.
c. Turn ignition switch ON.
d. Use X-431 3G diagnostic tester (the latest software) to record and clear DTCs stored in the HVAC control

panel assembly.

e. Turn ignition switch to LOCK and wait for a few seconds.
f. Turn ignition switch ON.
g. Use X-431 3G diagnostic tester to read DTCs stored in the HVAC control panel assembly again.

4

Check wire harness and connector (HVAC control panel assembly - body ground)

RT21311060

-

+

K-012

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

Multimeter

Connection

Condition

Specified

Condition

K-012 (22) - Body

ground

Always

No continuity

K-012 (34) - Body

ground

Always

No continuity

K-012 (35) - Body

ground

Always

No continuity

Repair or replace A/C wire harness and
connector

NG

5

Reconfirm DTCs

OK

Replace HVAC control panel assembly

NG

System operates normally

OK