Chery A15. Manual - part 46

 

  Index      Chery     Chery A15 - service repair manual

 

Search            

 

 

 

 

 

 

 

  

 

Content   ..  44  45  46  47   ..

 

 

Chery A15. Manual - part 46

 

 

 

6) Unstable idle speed at all time 

Yes 

Fix the indicated 

malfunction 

1 

Turn the ignition switch to “ON” 
position. Inspect with the diagnostic 
tester to see whether there is any 
malfunction information record. 

No 

Proceed to next step. 

Yes 

Repair or replace idle 

speed actuator 

2 

Verify that the EWD3 idle speed actuator 
or idle speed actuator with step motor is 
jammed. 

No 

Proceed to next step. 

Yes 

Inspect the wiring 

harness and plug in 

connector 

3 

Connect the ignition switch and verify 
that the links between water temperature 
sensor, idle speed step motor and ECU 
are properly connected. 

No 

Proceed to next step. 

Yes 

Proceed to Step 8 

4 

Run the engine at idle speed and cut off 
the cylinders one by one in order to 
observe whether the speed is decreasing 
or fluctuating. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

5 

Verify that the fuel injector of each 
cylinder functions normally. 

No 

Inspect the fuel injector 

and the wiring harness 

Yes 

Proceed to next step. 

6 

Verify that the resistance of each cylinder 
high voltage cable is normal. 

No Replace 

Yes Replace 

7 

Verify that the ignition coil is damaged. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

8 

Verify that the spark plug is normal. 

No 

Replace the spark plug 

Yes 

Proceed to next step. 

9 

Connect the fuel manometer valve. Short 
the 30# and 87# pins of the fuel pump 
relay to operate the fuel pump in order to 
verify that the fuel pressure is being 
maintained at about 350kPa. 

No 

Proceed to Step 13. 

Yes 

Proceed to Step 12. 

10 

Provide a voltage supply of 12V with 
special connector between the battery and 
the fuel injector, and verify that the fuel 
injector functions normally. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

11 

After washing and cleaning the fuel 
injector, verify again that it can function 
normally. 

No 

Replace the fuel injector

Yes 

Replace the fuel 

12 

Verify that the fuel is deteriorated or 
contaminated with water. 

No 

Proceed to Step 18 

Yes 

Proceed to next step. 

13 

Verify that the fuel pressure is lower than 
350kPa. 

No 

Proceed to Step 17. 

14 

Close the fuel manometer valve. Connect 

Yes 

Proceed to next step. 

 

G-72

 

 

the ignition switch again to re-operate the 
fuel pump in order to verify that the fuel 
pressure can be established. 

No 

Proceed to Step 16. 

Yes 

Replace the fuel pressure 

regulator 

15 

Open the fuel manometer valve and 
clamp the fuel return pipe with the fuel 
tube clamp to stop the fuel return in order 
to verify that the fuel pressure can be 
established quickly. 

No 

Repair or replace the fuel 

injector or fuel pipe 

Yes 

Repair or replace the fuel 

air inlet pipe 

16 

Verify that the fuel inlet pipe has any 
leakage or blockage. 

No 

Replace the fuel pump 

Yes 

Repair or replace the fuel 

return pipe 

17 

Verify that the fuel return pipe has any 
leakage or bending. 

No 

Replace the fuel pressure 

regulator 

Yes Clean 

18 

Verify that the sensing holes of the 
pressure and temperature sensor of air 
intake manifold have any blockages. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

19 

Run the engine at idle speed. When the 
coolant temperature reaches the 
temperature of activating the close- loop 
control, verify that oxygen sensor 
functions normally. (Fluctuating within 
the range of 0-1V) 

No 

Inspect the oxygen 

sensor and the wiring 

harness 

Yes 

Fix the leakage 

 

20 

Verify that the engine air intake system 
has any leakage. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

21 

Verify that the pressure of engine 
cylinder is normal. 

No 

Fix the malfunction 

Yes 

Replace the ECU. 

22 

Run the engine at idle speed until the 
coolant temperature reaches its normal 
range in order to verify that the ignition 
advance angle is normal. 

No 

Inspect other items 

 

 

G-73

 

7) Unstable idle speed during engine warm-up 

Yes 

Fix the indicated 

malfunction 

1 

Turn the ignition switch to “ON” position. 
Inspect with the diagnostic tester to see 
whether there is any malfunction information 
record. 

No 

Proceed to next step.

Yes 

Proceed to next step.

2 

Verify that the air filter is free of any blockage.

No Replace 

Yes 

Proceed to next step.

3 

Run the engine at idle speed. Verify that the air 
intake manifold pressure is maintained 
between 35-65 kPa during warm-up. 

No 

Fix the leakage of air 

intake system 

Yes 

Proceed to next step.

4 

Shut down the engine. Turn on the ignition 
switch and connect the adaptor between ECU 
and the wiring harness. Verify that the voltages 
at air intake temperature sensor, water 
temperature sensor, and ECU’s pins of 32# and 
33# (used as sensor power supply of 4.5-5V) 
are normal. 

No Service 

Yes 

Proceed to next step.

5 

Disconnect the connector of idle speed actuator 
before ending the engine warm-up and verify 
that the engine speed is changed. 

No 

Replace the idle 

speed actuator 

Yes 

Proceed to next step.

6 

Verify that the coolant temperature sensor is 
normal. 

No Replace 

Yes 

Replace the ECU. 

7 

Run the engine at idle speed until the coolant 
temperature reaches its normal range in order 
to verify that the ignition advance angle is 
normal. 

No 

Inspect other items 

 
 

 

 

 

 

 

 

 

 

 

 

 

G-74

 

8) Unstable idle speed or stall with load (A/C and etc.) 

Yes 

Fix the indicated 

malfunction 

1 

Turn the ignition switch to “ON” position. 
Inspect with the diagnostic tester to see 
whether there is any malfunction 
information record. 

No 

Proceed to next step. 

Yes 

Proceed to next step. 

2 

Turn on the A/C switch and connect the 
adaptor between ECU and the wiring 
harness. Measure and see whether the 
ECU’s A/C switch and pressure signal 
have any signal input. 

No 

Overhaul the A/C 

circuit. 

Yes 

Proceed to next step. 

3 

Verify that the pressure of A/C system, 
the magnetic clutch of compressor and 
A/C pump are normal. 

No 

Repair or replace. 

Yes 

Proceed to next step. 

4 

Turn the ignition switch to “ON” position. 
Verify that the voltages at ECU’s pins of 
65#, 64#, 67#, and 66# (output connected 
to idle actuator) are normal. 

No 

Inspect the control 

circuit. 

Yes 

Repair or replace the 

step motor. 

5 

Remove the step motor to verify that it is 
jammed or runs unfreely. 

No 

Proceed to next step. 

Yes 

Replace the ECU. 

6 

Start up the engine and turn on the A/C. 
Inspect with the diagnostic tester through 
the step amount of step motor to see 
whether the idle actuator functions 
normally. (The normal step amount will 
be provided otherwise) 

No 

Replace the idle 

actuator. 

 

 

 

 

 

 

 

 

 

 

 

 

 

G-75

 

 

 

 

 

 

 

Content   ..  44  45  46  47   ..