Chery S11 / Chery QQ. Manual - part 34

 

Chery QQ Service Manual                                                                Chassis System 

 

4、Too long for pedal travel 

  Possible cause 

Check any leakage in system 

·Fluid leak 
·Valve leak 
·Air in system 
·Disc damage 
·Bad manual brake 

 

                    Abnormal 

           

Normal 

 

 

 

Abnormal 

Normal

Normal 

Abnormal   

 

              

             abnormal 

          Replace manual brake                                

                              
 

abnormal 

                                  Re-exhaust 

 
 
                           abnormal  Replace HECU 
 
 
 

5、Must step on pedal hard 

Possible cause 

Check booster or pedal travel with conventional 

way 

·Bad booster 

·Bad valve 

 
 
 

 

 
 
 

Normal 

Check exhaust 

Normal 

Check valve leakage 

 

Normal 

Check valve

 

Check booster and pedal

travel

 

Check manual brake 

Check disc 

Check any leakage 

Screw connector

 

Replace disc 

Replace HECU

 
 
 

 
 

49

   

                                                                                                                                                                                                       

 

Chery QQ Service Manual                                                                Chassis System 

 
6、No DTC put out( cannot communicate with tester) 

Possible cause 

Open in ABS ECU source circuit or diagnosis 

circuit 

·Fuse burn out 

·Diagnosis wire 

loose or damage 

·ABS ECU damage 

·Tester problem 

 
 

No

 

 

 

Yes

 

   

 

 

Fix tester and try

again 

Can tester communicate with

other MK20 ABS ECU 

Abnormal

                  

Replace

         

Check ABS fuse 

Norma

                            

No

                                   

Abnormal

 

Yes

On 

 

                     

              

 
 

No 

Fix diagnosis plug or harness   

 
 
 
 

Any display on tester 

Check source wire,

ground wire, and

connector 

Check terminal is conducted

with diagnosis terminal
（MK20I/E : terminal 7） 

Fix or

replace 

    
Replace ABS ECU 

 

 
 
 
 
 
 
 
 

 
 

50

   

                                                                                                                                                                                                       

 

Chery QQ Service Manual                                                                Chassis System 

 
8、ABS inspection 

Terminal 

Item 

Key 
position  MK20I/E 

Specifications  Unit 

Battery and motor 
voltage 

OFF 

25-8 

10.1-14.5 

V 

Battery and solenoid 
voltage 

↑ 

9-24 

↑ 

V 

Source isolation 

↑ 

8-4 

0.00-0.5 

V 

Ground isolation 

↑ 

8-24 

↑ 

V 

Source 

ON 

8-4 

10.0-14.5 

V 

OFF 

Light off 

 

ON 

ECU not 
connected 

Light on 

 

OFF 

Light off 

 

ABS light 

ON 

Connect ECU 

Light on for 1.7 
sec and off 

 

Brake light pedal not 
push down 

ON 

8-18 

0.0-0.5 

V 

Brake light pedal 
push down 

ON 

8-18 

10.0-14.5 

V 

Front left sensor 
resistance 

OFF 

1-2 

1.0-1.3 

KΩ 

Front right sensor 
resistance 

OFF 

19-20 

1.0-1.3 

KΩ 

Rear left sensor 
resistance 

OFF 

5-6 

1.0-1.3 

KΩ 

Rear right sensor 
resistance 

OFF 

22-23 

1.0-1.3 

KΩ 

Front left sensor out 
put voltage 

OFF 

1-2 

3.4-14.8 

mV/HZ 

Front right sensor 
resistance out put 
voltage 

OFF 

19-20 

3.4-14.8 

mV/HZ 

Front left sensor out 
put voltage 

OFF 

5-6 

>12.2 

mV/HZ 

Rear left sensor out 
put voltage 

OFF 

22-23 

>12.2 

mV/HZ 

Sensor out put 

voltage ratio 

Max peak voltage 

 

    ≦ 2 

Min peak voltage 

 

 
 

 
 

51

   

                                                                                                                                                                                                       

 

Chery QQ Service Manual                                                                Chassis System 

 

9、Check ABS 
（1） Check the out put voltage of speed sensor 
1. Check if the clearance between speed sensor and teeth ring is satisfied with 
specification. 
2. Lift the wheel and release manual brake. 
3. Remove ABS harness and measure the points of connector. 
4. Run the wheel at speed of 1/2 RPM and measure the out put voltage. 
             MK20 I                                  MK20 I/E 
Front left wheel terminal 4 – 11       terminal 1 - 2 
Front right wheel terminal 3 – 18      terminal 19 – 20 
Rear left wheel terminal 2 – 10        terminal 5 - 6 
Rear right wheel terminal 1 – 17       terminal 22 – 23 
5. If the voltage is not with specification, the causes may be: 

 The clearance between sensor and teeth ring is too big. 
 Sensor malfunction. 
 The resistance of sensor is 1.0—1.3 k. 
 Distortion of teeth ring. 

 
10、Removal and installation 
(1)、 Spare parts offering  
* HECU assembly dry type； 
* HCU  and ECU  separate HCU  wet type 
(2)、Precaution on removing 

 Repair the faults after find the 

 cause for malfunction with test  
instrument 

 

 Only open the package before  

installation. 

 Only use original parts. 
 Only clean with soft cloth. 
 Don’t use compressed air or move the 

vehicle when ABS is working. 

 Block the outlet for each pipe after 

removing the parts. 

 Please use DOT 4 brake fluid. 
 Dip the seal and o-ring with brake liquid. 
 Check the function of ABS and conventional brake system is normal after 

repairing. 

 Check if any leakage on each connector. 

(3)、MK20-I HECU assembly Removal  

 Turn off ignition switch and disconnect (-) wire on battery. 
 Remove the harness from ABS assembly. 

 

 
 

52