Chery A15. Manual - part 256

 
 
2. Component parameters: 
Working temperature: -40 ～ 150℃ 
Working voltage: 4.5 ～13 V 
Working clearance: 0.3 ～ 2 mm 
Wiring terminals:  
1 – Signal, 2 – signal grounding, 3 - +5V 
3. Fault diagnosis 
Tips: All the following judgments are based 
on the normal operation of the vehicle, wire 
harness and other system components. 

•  The faults are discovered by the 

system and displayed on the diagnostic 
instrument. 

•  Overvoltage damage; 
•  Over clearance between the sensor and 

the signal wheel; 

•  Incorrect relative position or 

displacement of the signal wheel to the 
camshaft  

 
 
Eight. Vehicle speed sensor (VSS) 
1. Functions and principles 
Vehicle speed signals are provided by the 
vehicle speed sensor. ECM receives the digital 
square waves whose amplitude is 5 – 14V.  
The system demarcation uses the signals to 
improve the vehicle driving performance. 
Wiring terminals:  
1 – 12V power source, 2 – grounding, 3 – 
vehicle signal 
Fixing: it is fixed behind the gearbox casing. 
 
 
 
 
 
 
 
 
 
 
 
 

 

 
 
2. Fault diagnosis 
Tips: All the following judgments are based 
on the normal operation of the vehicle, wire 
harness and other system components. 
The faults are discovered by the system and 
displayed on the diagnostic instrument. 
Signal failure causes includes: sensor damage, 
fitting detachment, wire harness fault or other 
human factors. The system will accordingly 
restrict the vehicle driving component 
parameters, or the driving performance will 
worsen.  
 
 
Nine. Knock sensor (KS) 
1. Function and principles 
Knock sensor is a kind of electronic vibrating 
sensor and fixed on a sensitive position on the 
engine cylinder body for sensing the knock of 
the engine.  
ECM can detect the knock intensity through 
the knock sensor and then correct the ignition 
advance angle to effectively control the knock, 
optimize the engine power generation, save 
fuel cost and minimize exhaust.  
The system uses flat response knock sensor 
and the ECM filters the received signals; as 
the sensor signal is relatively weak, the wire 
lead shall be shielded.  
Wiring terminals: 

Knock

1 – Signal, 2 – Grounded through the 
shielding 
Fixing: the knock sensor is fixed onto the 
middle of the engine cylinder and below the 
air intake manifold.  
2. Component parameters: 
Output signals: 
Vibrating frequency  Output signals 
5kHz       17～37mV/g 
8kHz       increase by +15％at 5kHz 
13kHz      increase by +30％at 5kHz 
 
 
 

 

 
18kHz      double at 13kHz and >17mV/g at 
any moment 
Frequency range for response: 3 – 18kHz 
Capacitance: 1480～2220pf at 25℃, 1000Hz 
Resistance: >1M

Ω at 25℃ 

Working temperature: -40～150℃ 
3. Fault diagnosis 
Tips: All the following judgments are based 
on the normal operation of the vehicle, wire 
harness and other system components. 
The faults are discovered by the system and 
displayed on the diagnostic instrument. 
The signal cable is not shielded or the shield has ground fault;  
Sensor fixing torque is bigger than 200N.m; 
Bad gasoline quality; 
Faults of engine turning parts (like water pump); 
Extra fuel in the engine; 
Striking on the engine bracket; 
Sensor faults. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 

Section Three. Air intake Control System 

 
 
One. General description 
1. Functions and principles 

•  The function of the air intake control system is to provide proper air flow required 

by the engine power output. The control of air inflow consists of active control 
and system automatic control; 

•  Active control refers to the driver’s active adjustment of throttle opening and 

control of the engine power output as required.  

•  System automatic control refers to the automatic control of air inflow as per the 

feedback from the closed-loop control monitor to stabilize the operation of the 
engine (e.g. engine idle speed closed-loop control). 

2. System structure 
  

阀体

节气门传感器

怠速控制阀

进气控制系统

(

)

节流阀体

 
 
 
 
 
 
 
 
 
 
Air inflow control system (throttle) 
Valve body 

Throttle sensor 

Idle speed control valve 

 
Two. Throttle assembly 
1. Functions and principles 
The throttle assembly is used to control the air inflow into the engine in operation. It is 
the fundamental channel through which the driver controls the fuel injection system.  
The throttle assembly consists of throttle body, valve, pull rod assembly, throttle position 
sensor, idle speed control valve, etc;  
Fixing: the throttle body is fixed in front of the air intake manifold.