Chery QQ6 (S21) / S12LHD. Manual — part 255

11.13 Accelerator Pedal Position Sensor Failure

Failure codes: P2106, P2122, P2123, P2127, P2128, P2138

No.

Operating steps

Result

Follow up steps

1

Put the ignition switch to “ON”.

Next step

Yes

Next step

2

Pull out accelerator pedal position sensor joint on

harness, and then use a multimeter to check if an

around 5V voltage signal is present between 3#,

6# pins of this joint and ground wire.

No

Check the circuit

Yes

Check the circuit

3

Pull out accelerator pedal position sensor joint on

harness, and then use a multimeter to check if it is

short or break circuit between 3#, 6# pins of this

joint and 32#, 33# pins of ECU.

No

Next step

Yes

Check the circuit

4

Pull out accelerator pedal position sensor joint on

harness, and then use a multimeter to check if it is

short or break circuit between 2#, 5# pins of this

joint and 36#, 35# pins of ECU.

No

Next step

Yes

Check the circuit

5

Pull out accelerator pedal position sensor joint on

harness, and then use a multimeter to check if it is

short or break circuit between 4#, 1# pins of this

joint and 16#, 40# pins of ECU.

No

Next step

Yes

Next step

6

Use a diagnostic tester to read signal output of

accelerator pedal position sensor, and then check

if signal 1 increases as opening of accelerator

pedal increases.

No

Replace the sensor

assembly

Yes

Check other part

7

Use a diagnostic tester to read signal output of

accelerator pedal position sensor, and then check

if signal 2 increases as opening of accelerator

pedal increases.

No

Replace the sensor

assembly

Note: This pedal is an integrated circuit device, which can not be processed through repair; therefore,

during maintenance process, the service station can maintain it by means of part replacement and can not

disassemble the sensor.

11.14 Double Brake Switch

Failure codes: P0571, P0504

No.

Operating steps

Result

Follow up steps

1

Put the ignition switch to “ON”.

Next step

Yes

Next step

2

Pull out brake switch joint on harness, and then

use a multimeter to check if it is short or break

circuit between 1#, 2# pins of this joint and 21#,

58# pins of ECU.

No

Check the circuit

Yes

Next step

3

Close the ignition switch, and then check if an

around 12V battery voltage is present on 3# pin of

the switch joint.

No

Check the circuit

Yes

Next step

4

Open the ignition switch, and then check if an

around 12V battery voltage is present on 4# pin of

the switch joint.

No

Check the circuit

Yes

Next step

5

Release brake pedal, disconnect sensor connector,

and then check if 1# and 3# pins cut off.

No

Replace the brake

switch

Yes

Next step

6

Release brake pedal, disconnect sensor connector,

and then check if 2# and 3# pins conducts.

No

Replace the brake

switch

Yes

Next step

7

Apply brake pedal, disconnect sensor connector,

and then check if 1# and 3# pins conducts.

No

Replace the brake

switch

Yes

Check other part

8

Apply brake pedal, disconnect sensor connector,

and then check if 2# and 4# pins cut off.

No

Replace the brake

switch

11.15 Theft-proof Control System Failure

No.

Operating steps

Result

Follow up steps

1

Insert the ignition key into the ignition lock.

Next step

Yes

Check other part

2

Put the ignition switch to ON position, and then

observe if engine failure indicator lamp or EPC

lamp works normally (quick flash of failure

indicator lamp or EPC lamp indicates a abnormal

condition).

No

Next step

Yes

Remove the failure

and clear the DTC

3

Connect a diagnostic tester to the system, and then

enter corresponding diagnostic program unit to

check if DTC exists in the system.

No

Next step

Yes

Next step

4

Pull out theft-proof module joint on harness, and

then use a multimeter to check if an around 12V

operating voltage is present on A1#, A4# pins of

the joint when ignition switch is under ON state.

No

Check the circuit

Yes

Check the circuit

5

Pull out theft-proof module joint on harness, and

then use a multimeter to check if such electric and

circuit failures as short circuit and break circuit

exist in the circuit between A5#, A8# pins of this

joint and 31# and 71# pins of ECU.

No

Next step

Yes

Check the circuit

6

Pull out theft-proof module joint on harness, and

then use a multimeter to check if poor contact

exists between A2# pin of this joint and ground

wire of the vehicle.

No

Next step

Yes

Check the circuit

7

Pull out theft-proof module joint on harness, and

then use Ohm Shift of the multimeter to check if

the circuit between B1#, B2#, B3# pins of this

joint and the coil exists.

No

Replace

the

theft-proof module

12. Steps for Implementation of Failure Diagnosis by Engine

Symptom

12.1 Perform Preliminary Inspection First before Following the Steps for
Implementation of Failure Diagnosis by Engine Symptom.

(1) Make sure that ECU and failure indicator lamp (or EPC lamp) have no off-normal
phenomenon (excluding the models that have no failure indicator lamp).
(2) Use a failure diagnostic tester to check and make sure no failure information record
exists.
(3) Employ failure diagnostic tester to check that hot idle data from electronic control
system fall within normal scope.

Hot idle speed parameter table:

Name

Parameter

Air intake temperature

20-70℃

Battery voltage

12-14V (affected by engine revolution)

Temperature of engine coolant

80-90

(normal operating temperature)

℃

Position of accelerator pedal

0%~99.00%

Air-fuel ratio control integrator

5%-5%

Ignition advance angle

5-10

°

(

may change with fluctuation of

engine revolution)

Outer corner of throttle

0%~99.61%

Fuel injection time

2-7ms (has a strong relation with engine
revolution)

Engine revolution n

Expected idle speed ± 50rpm

Duty cycle of canister control valve

0%~99.9%

Self-adapting value of air-fuel ratio
control

0.95-1.05

Self-adapting value of air-fuel ratio
control

120-140

Intake manifold absolute pressure

350-650hPa

Voltage of oxygen sensor

Quickly fluctuates at 0.1-0.9V

Air intake pressure

(4) Validate that the failure effect the owner complained exists and then locate the exact
position of the symptom. Please note that the information provided by the customer is
very important, especially the failure symptoms, occurrence time, position and if any
other failure symptoms occurred before; these information can help technical personnel
rapidly and effectively judge the failure, thus increasing maintenance speed and
improving maintenance quality.
Then check the appearance: