Chery A15. Manual - part 255

CTS

5 V

GND

 

A/D

M

EC

2. Component parameters 
Working voltage: 5V DC 
Working temperature: -40 ～ 135

°C 

Circuit diagram:  
At 20 ～ 30

°C, the resistance is 3560 ～ 2260 Ω 

At 90～ 100

°C, the resistance is 120～180Ω 

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. 
Check water temperature sensor resistance; 
Check if the cylinder cover temperature at the 
water temperature sensor matches the temperature 
displayed on the ADC2000 decoder.  
 
 
Five. Throttle position sensor 
1. Functions and principles 
The throttle position sensor is of a linearly variable 
resistance structure and its sliding terminal is driven 
by the throttle shaft;  
The resistance signal given by the sensor to the ECM 
will be different for different throttle opening. The 
system will judge real time engine load and dynamic 
variations according to the output signals and their 
changing speed:  
Wiring terminal: A - +5V, B – signal grounding, C – 
throttle position signal; 
Fixing: the throttle position sensor is located on 
the throttle assembly and is coaxal with the 
throttle pull rod and throttle.   
2. Component parameters:  
Range: 7% - 93% opening 
Working voltage: 5

±0.1V 

Closed throttle: reference voltage 12%

±5% 

 
 
 
 
 
 
 
 
 

 

Wide open throttle: 83%～93% 
A, B resistance: 3k～12k

Ω 

Working temperature: -40～150ºC 
 
 
 

 

Pin 

Idle speed voltage (V) 

Pin 

Idle speed voltage (V) 

A 5 

B 0 

C 

0．46～4.6 (wide open) 

 

 

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 resistance between Terminal A and B is 3k～12k 

Ω; 

The measurement of resistance variations between C and A or C and B shall be smooth.  
Check the mechanical adjustment between the accelerator pedal and throttle. 
 
 
Six. Oxygen sensor 
1. Functions 
The oxygen sensor is one important component in the closed-loop fuel control system. It 
adjusts and maintains an ideal AFR and optimizes the transfer efficacy of the three-way 
catalyst. When the AFR becomes lower or higher, the oxygen content of the exhaust will 
increase or decrease respectively and the oxygen sensor output voltage will decrease and 
increase respectively as well. And the AFR information is sent to the ECM then.  
The rear and front oxygen sensors have the same structure and are used to monitor 
the working efficacy of the accelerant.  
The oxygen sensor has zirconia as its sensitive material which consists of the empty part 
and the external sensitive part. After the zirconia component is heated up (>300℃) and 
actuated, the reference air will go into the empty part through the conduit. The exhaust 
will go through the external pole of the zirconia. The oxygen ions shift from the center of 
zirconia towards the external pole to form a simple atomic battery and create voltage 
between two poles; zirconia can change this output voltage according to the presence of 
oxygen in the exhaust and thus judging the oxygen content in the exhaust. The oxygen 
sensor is designed to generate a substantial voltage variation around the theoretical AFR 
(14.6:1), which is beneficial to the ECM’s accurate judgment of the AFR.  
 
 
 
 
 
 
 

 

 
2. Features 
- Water proof; 
- No need for air filter; 
- High temperature, high voltage and thermal 
impact resistant 
- Superb low temperature parameters 
- Superb anti-intoxication capability 
- Heater of low energy consumption 
- Teflon insulating wires and stainless cast 
components are adopted for the oxygen sensor. 
3. Component parameters 
Component parameters 

Temperature 

260℃ 450℃ 595℃ 

High ARF output voltage (mV) 

>800 

>800 

>750 

Low ARF output voltage (mV) 

<200 

<200 

<150 

Response time from low AFR to high 
AFR (ms) 

<75 <75 <50 

Response time from high AFR to low 
AFR (ms) 

<150 <125 <90 

Internal resistance (

Ω) 

<100K 

 
Maximum working temperature (continuous): 
- Air exhaust temperature: < 930℃ 
- Fixing seat: < 600℃ 
- Casing hexagon: < 500℃ 
- Wire and protective jacket: < 275℃ 
- Wire sealing gasket: < 250℃ 
- Fittings: < 125℃ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 
- Storage temperature: -40 ～100℃ 
Working conditions: 
- Exhaust temperature: 200 ～850℃ 
- The foreign matter content in the fuel is allowed 
to be low than: 
Lead – 0.005g/l 
Phosphor – 0.0002g/l 
Sulfur – 0.04% (weight ratio) 
Silicon – 4ppm 
MMT – 0.0085g/l 

Front Oxygen Sensor 

- The engine oil consumption shall not be more 
than 0.02l/h; 
Fixing position 
- Front oxygen sensor is located between the 
throttle and the three-way catalyst and the rear 
oxygen sensor is behind the three-way catalyst.  
Wiring terminal: 
A – low signal, B – high signal 
C and D – connected with the power source for 
heating 
 
 
4. Fault diagnosis 
Tips: All the following judgments are based on 
the normal operation of the vehicle, wire harness 
and other system components. 

Rear Oxygen Sensor 

The faults are discovered by the system and 
displayed on the diagnostic instrument. 
Not enough times to change from high AFR to 
low AFR, intoxication with heavy metals (like 
lead and manganese), phosphor and sulfur or 
damage by overheating.  
 
 
 
Seven. Camshaft Position Sensor (CAM) 
1. Functions and principles 
The camshaft position sensor is a Hall sensor. It is 
located in the front of the camshaft and works 
together with the signal wheel on the camshaft. 
The signal wheel corresponds with a specific 
position of the engine and ECM detects the digital 
voltage signals from the sensor to determine the 
working cylinders of the engine and control them.  
Fixing: it is fixed near the camshaft.