Chery QQ6 (S21) / S12LHD. Manual — part 111

12.2 The Engine Does not Rotate or Rotates Slowly when Starting

No.

Operating steps

Result

Follow up steps

Yes

Next step

1

Use a multimeter to check if a voltage around

10-12.5V is present between two battery

terminals.

No

Repair

or

replace

the

battery

Yes

Next step

2

Put the ignition switch to “ON”. Use a

multimeter to check if a battery voltage around

10-12.5V is present on the terminal on the

ignition switch that connects with anode of

battery.

No

Repair

wiring

terminal

or

replace cable

Yes

Next step

3

Maintain ignition switch at START position,

and then use a multimeter to check if a voltage

above 8V is present on the terminal on the

ignition switch that connects with pull in

winding of starting motor.

No

Replace

the

ignition switch

Yes

Next step

4

Put the ignition switch at start position, check

the anode terminal of starting motor by

multimeter and observe the voltage if it is above

8V.

No

Repair

wiring

terminal

Or

replace

cable

Yes

Repair

or

replace

the

starting motor

5

Check if it is short circuit or break circuit in the

starting motor.

No

Next step

Yes

Troubleshootin

g

6

Check if there is jammed by poor lubricating.

No

Next step

Yes

Replace

with

appropriate oil

7

If the failure is happened in winter time, check if

it is because of the wrong engine lubricant and

gearbox oil causes the big resistance of the

starting motor.

No

Check if other

systems

are

normal

Note: When this problem occurs, mainly inspect voltage, starter and ground system. In
modern sedan, lubricant has little effect on startup of the vehicle, so, basically, it needs
not to allow for lubricant problem, but the problem if the engine has too large self
resistance should be taken into consideration.

12.3 When Starting, Engine Can be Dragged to Rotate but Can not Start

with Success.

No.

Operating steps

Result

Follow up steps

Yes

Remove

the

failure displayed

1

Put the ignition switch to “ON”. Use a failure

diagnostic tester to check if any failure

information record exists.

No

Next step

Yes

8

2

Pull out cylinder distribution wire, connect

spark plug with the distance between electrode

of spark plug and engine body as 8-10mm, use

the starting motor to drag the engine to rotate,

and then check if blue-white high-voltage spark

occurs (disconnect all injection nozzles on the

engine).

No

Next step

Yes

Next step

3

Check if resistance value of ignition cable is

normal (can not exceed 16kΩ).

No

Repair, replace the

ignition cable.

Yes

Replace

4

Check ignition coil and ignition cable for burn

through, damage and crack.

No

Next step

Yes

Replace

5

Check if ignition cable is normal.

No

Next step

Yes

Next step

6

Check if the ignition coil is working normally.

No

Replace

Yes

Next step

7

Check if connectors of ignition coil and

ignition cable are connected properly.

No

Connect

the

connectors

properly

Yes

Next step

8

Put the ignition switch to “ON”. Check if fuel

pump relay and fuel pump can keep working for

a period of time.

No

Overhaul the fuel

pump circuit

Yes

Next step

9

Connect fuel manometer valve. Short 30# and

87# pins of fuel pump relay to make the fuel

pump run, and then check if fuel pressure is

around 400kPa.

No

13

Yes

12

10

Pull off the fuel distributing pipe and the fuel

injector; pull off the joints of fuel injector on the

harness one by one. And supply the voltage of

12 V from battery to fuel injector directly and

look if the fuel injector can inject normally.

No

Next step

11

Clean out the fuel injector and observe if it can Yes

Next step

work correctly.

No

Replace the fuel

injector

Yes

Replace fuel

12

Check if fuel is bad or moisture.

No

18

Yes

Next step

13

Check if the fuel pressure value is below 400

kPa.

No

17

Yes

Next step

14

Close the fuel manometer valve. Re-engage the

ignition switch to let the fuel pump run for a

period of time, and then check if fuel pressure

can be built up.

No

16

Yes

Check other part

15

Open the valve of fuel gauge and clamp the oil

return pipe by oil return baffle so that the oil can

not return. Check if the oil pressure occurs

immediately.

No

Repair or replace

the fuel pump

Yes

Repair or replace

oil intake pipe

16

Check if there is leakage or jam in oil intake

pipe.

No

Replace oil pump

Yes

Repair or replace

oil return pipe

17

Check if the oil return pipe is bended or

jammed.

No

Replace

fuel

pressure regulator

Yes

Repair or replace

the harness

18

Check if it is break or short circuit between 1#,

2# pins of crankshaft position sensor and 34#,

15# pins of ECU.

No

Next step

Yes

Repair

19

Check if the part of air intake system is leaking.

No

Next step

Yes

Repair or replace

20

Check if air flow meter works normally.

No

Next step

Yes

Next step

21

Check if the coolant temperature sensor is

working correctly.

No

Repair or replace

Yes

Remove

the

mechanical failure

22

Check if the reason for the failure on starting is

about mechanism, such as much cylinder

clearance, cylinder leaking, and so on.

No

Replace ECU

Note: When checking this problem, if all parts in electronic fuel injection system are
normal, consider if mechanical part of the engine works normally, or if cylinder
pressure is normal and if air leakage exists and so forth.

12.4 Warm Starting Difficulty

No.

Operating steps

Result

Follow up steps

Yes

Remove the failure

displayed

1

Put the ignition switch to “ON”. Use a special

diagnostic tester to check if any failure

information record exists.

No

Next step

Yes

Next step

2

Connect fuel manometer valve. Short 30# and 87#

pins of fuel pump relay to make the fuel pump

run, and then check if fuel pressure is around

400kPa.

No

9

Yes

Next step

3

Disconnect the connecting oil pipe and turn off the

ignition switch. Observe the voltage of fuel system

and look if it is around 300 kPa after an hour.

No

Repair

the

fuel

system

to avoid

leakage

Yes

Replace

fuel

pressure regulator

4

Put the connecting oil pipe through, use fuel tube

clamp to intercept the oil return pipe, meanwhile,

close the fuel manometer valve. Turn off the

ignition switch, after one hour, observe if pressure

of fuel system still can maintain at around 400kPa.

No

Next step

Yes

Replace the injector

and fuel pipe

5

Check if there is fuel leakage of fuel injector and

oil pipe.

No

Next step

Yes

Check

coolant

temperature

and

circuit

6

Pull out water temperature sensor joint and start

the engine. Observe if the engine can start with

success.

No

Next step

Yes

Next step

7

Connect an adaptor between ECU and harness,

check if a voltage around 5V is present on 39#,

17# pins, meanwhile, check if the resistance value

of water temperature sensor is within normal

scope.

No

Repair or replace

the harness

Yes

End

8

Replace ECU and perform warm start again;

observe if the engine can be started successfully.

No

Replace ECU

Yes

Next step

9

Check if there is jam or bending of fuel pipe and if

the pressure regulator valve of oil pump is

working correctly.

No

Repair or replace

Yes

Next step

10

Check if there is battery voltage between the plugs

of oil pump with multimeter.

No

Repair or replace

fuel pump relay and

wires

Yes

Next step

11

Try to replace the fuel pump and see if the system

can return to normal.

No

Replace fuel pump