Chery A11. Manual - part 168

 

Maintenance Manual for Chery·Windcloud   

MOTOROLA EFI System

 

2. Throttle Position Sensor 
 
Purpose: MOTOROLA TPS sensor is 
designed to provide ECU with information of 
throttle angle and angle rate. As per such 
information，ECU could obtain engine load 
information and operating mode information 
(for instance: start-up, idle speed, reverse, part 
load and full load) as well as acceleration and 
deceleration information. This sensor is 
three-wire style, and the throttle opening can be 
detected by ECU via monitoring voltage 
variation.  
 
 
 
 
Composition and principle: the said sensor’s 
structure is of sliding resistance slice style, 
ECU obtains throttle opening signal by 
monitoring voltage at the signal output terminal 
via comparison circuit inside computer. 
Voltage signal is not received directly inside 
ECU, instead, output/input signal ratio is tested, 
thus preventing from signal fluctuation due to 
voltage fluctuation.   

 

2

 
 
 
 
Failure diagnosis:   
Throttle position sensor signal above measuring 
range;

 

Throttle position sensor signal below 
measuring range;   
Throttle position sensor signal line short 
circuit;  
Throttle position sensor signal line short 
circuit;  

 

Installation:  allowable tightening torque 
for fastening screw is 1.5Nm-2.5Nm. 

 

 

 

Throttle position sensor 

（2 refers to throttle position sensor） 

 

Throttle position sensor 

Circuit diagram of throttle position sensor 

 

Pins:  
 

1 sensor signal ground (ECU B17#) 

2 5Vpower source (ECU B32#) 

3 sensor signal (ECU B16#) 

     

 
 

Troubleshooting:  mainly check if there is 

short circuit or open circuit on the connection 

between 3 lines on senosr and ECU.   

If there is short circuit, open circuit or 

grounding between sensor wire harnesses.   

Check between sensor signal terminal and 

ground wire with multimeter when swtiching 

on/off throttle to see if pulse occurs.   

 

 

Maintenance Manual for Chery·Windcloud   

MOTOROLA EFI System

 

 

3

3. Coolant Temperature Sensor TF-W

 

 
 
Purpose: this sensor is designed to provide 
coolant temperature information. To provide 
engine ECU with water temperature signal used 
for control of ignition timing and fuel injection 
pulse width in startup, idle speed and normal 
operation.  
 
Composition and principle: this sensor is a 
thermistor of negative temperature coefficient 
(NTC) with resistance value decreasing with 
the increasing of coolant temperature and vice 
versa except linear relation. ECU monitors 
water temperature variation as per sensor 
output signal and via comparison circuit inside.   
 
 
 
Failure diagnosis: water temperature signal 
above limit value;   
Water temperature signal below limit value;   
Short circuit or open circuit occurs in water 
temperature sensor line.   
 
 
Limiting data: 2.5±5%KΩ 
 
 
Installation hint: tightening torque is 15Nm in 
maximum.   
 
Hints: the vehicle is equipped with 2 water 
temperature sensors, one is single-pin water 
temperature sensor, providing the water 
temperature gauge with water temperature 
signal; the other is double-pin, providing the 
engine ECU with water temperature signal.   
 

 

Coolant temperature sensor 

 

Water temperature sensor 

 

Circuit diagram of coolant temperature sensor

 

 
Pins:  this sensor has 3 pins, which can 

interchange for use.   

1 coolant temperature sensor signal (ECU 

B10#) 

2 sensor signal ground (ECU B23#) 

 

 
Troubleshooting: mainly check if there is 

short circuit or open circuit on the connection 

between 3 lines on senosr and ECU as well as 

instrument.  

If there is short circuit, open circuit or 

grounding between sensor wire harnesses.   

Line grounding or defect grounding is liable 

to cause engine water temperature gauge to 

indicate excessive temperature. 

 

 

Maintenance Manual for Chery·Windcloud   

MOTOROLA EFI System

 

 

4

4. Knock Sensor KS 
 
Purpose:  this sensor is designed to provide 
ECU with engine knocking information so as to 
carry out knocking control.   
 

 

Composition and principle: knock sensor is a 
sort of vibration acceleration sensor, which is 
fixed on engine cylinder block. ECU judges the 
occurrence of engine knocking by using 
vibration frequency signal outputed by knock 
sensor, which goes through filtration.   
 
 
Failure diagnosis: ECU monitors on various 
sensors, actuators, power amplification circuits 
and sensing circuits. In case any of the 
following situations occurs, failure mark of the 
knock sensor is set.   
Knock sensor failure 
Knocking control data processing circuit failure 
Cylinder-detecting signal is unreliable 
After failure mark of knock sensor being set, 
knocking closed-loop control is shut down, 
reduceing a safety angle from the ignition 
advance angle stored in ECU. When error 
frequency cuts down to below setting value, 
failure mark restores. 

 

 
 

Installation hint: tightening torque is 
20±5Nm. 

 

 
 
 
 
 

 

1. Knocking block
2. Casing   

3. Piezoelectric ceramics 
4. Contactor   
5. Electric connection

 

Knock sensor with cable 

 

Knock sensor 

Circuit diagram of knock sensor 
 

Pins:  

1 Knock sensor signal 1(ECU B2#) 

2

 

Knock sensor signal 2 (ECU B3#) 

 
Troubleshooting:  mainly check if there is 

short circuit or open circuit on the connection 

between 2 lines on senosr and corresponding 

ECU pins.   

If gasket is added during installation; if 

tightening torque is proper.   

If there is stitching defect between sensor and 

cylinder, or if there is foreign matter between 

them.  

 

 

Maintenance Manual for Chery·Windcloud   

MOTOROLA EFI System

 

 

5

5. Oxygen Sensor 
Purpose: this sensor is designed to provide the 

information that if there is surplus oxygen after 

full combustion of fuel, which is injected into 

engine cylinder in the intake air. ECU, when 

applying this information, can carry out fuel 

quantitative closed-loop control so as to 

achieve utmost conversion and purification of 

the three major toxic elements (HC, CO and 

NO

X

) in the engine exhaust with the application 

of three-way catalytic converter.   
Composition and principle: sensing element 

of oxygen sensor is a porous ceramic pipe, the 

outer side of pipe wall is surrounded by engine 

exhaust, while inner side vents to atmosphere. 

According to inside and outside oxygen 

concentration difference, sensor figures out 

indirectly the fuel injection pulse width, and 

transfer to ECU, and the ECU controls the 

injection again.   
 

The working voltage of oxygen sensor 

fluctuates between 0.1-0.9V, 5-8 variations in 

10 seconds is required; if lower than such 

frequency value, it shows that the sensor is 

aged, and needs replacement. The said sensor is 

unrepairable.  

 

Failure diagnosis: ECU monitors on various 

sensors, actuators, power amplification circuits 

and sensing circuits. In case any of the 

following situations occurs, failure mark of the 

oxygen sensor is set.   

Accumulator voltage is unreliable 

Manifold absolute pressure signal is unreliable 

Engine coolant temperature signal is unreliable.   

Injector driver stage failure 

After oxygen sensor failure mark is set, fuel 

quantification closed-loop control is shut down, 

and the primitive fuel injection time stored in 

ECU is used to carry out fuel quantification.   

 

Installation hints: the tightening torque of 

oxygen sensor is 50-60Nm, a layer of rust 

preventive oil shall be applied on oxygen 

sensor after replacing so as to prevent from 

incapable removal in case of rust.   

 
Troubleshooting:  mainly check if the plug 

connection of several wires on the sensor is 

in good condition, and if there is short circuit 

or open circuit.   

Generally, sensor damage is caused by 

plumbum and phosphorus poisoning, so pay 

attention to fuel quality, meanwhile excessive 

consumption of engine oil is liable to result 

in sensor failure.   

The variation frequency of oxygen sensor 

shall not be lower than a certain value within 

a specified time.   

 

Oxygen sensor 

 

Main 
power 

Oxygen sensor

Circuit diagram of oxygen sensor 

Oxygen sensor has a cable, the other end of 

which is electric connection. The outside of 

sensor is wrapped with asbestos fireproof 

covering.  

 
There are 4 pins on the joint:   

1# connecting with heating power supply and 

main relay;   

2# connecting with heating control (ECU B16); 

3# connecting with sensor signal anode (ECU 

B1#); 

4# connecting with sensor signal cathode (ECU 

B23#).

 

 

Interior structure of oxygen sensor