Chery A15. Manual - part 254

 

Section Two. Sensor Signal Collection System 

 
 
One. Description 
The function of signal collection system is to provide to the ECM the working status of 
the engine and vehicle and the driver’s requirements on power and auxiliary functions.  
The following signals are currently adopted for the system: 
- Engine speed and crank shaft position sensor 
- Camshaft position sensor 
- Knock sensor 
- Oxygen sensor 
- Throttle position sensor 
- Air intake manifold pressure sensor 
- Air intake temperature sensor 
- Engine cooling fluid temperature sensor 
- Vehicle speed sensor 
 
 
Two. Engine speed and crank shaft position sensor (CPS) 

No. 20

No. 50

No. 01

No. 01

1. Functions and principles 
The crank angle sensor output is used to determine crank 
shaft position and turning speed. 
The engine speed and crank shaft position sensors are 
electromagnetic sensors and located near the crank shaft, 
working together with the 58x gear ring on the crank 
shaft. When the crank shaft turns, the 58x gear tip and 
gear trough passes the sensor in different length. The 
sensor feels the magnetic resistance variations and gives 
out variable output signals. The notch on the 58x gear 
ring corresponds with the upper limit of the engine. 
When the first cylinder upper limit is reached, the sensor faces the lower edge of the 20

th

 

tooth of the 58x gear ring. ECM uses this signal to determine the position and speed of 
the crank shaft.  

 
 

 

 
2. Component parameter 

 No power source needed; 
 Temperature range: -40 ～ 150℃ 
 Output voltage: increase with the increase of the 

turning speed (400 mV @ 600 rpm); 

 Clearance with the 58x gear ring: 0.3 – 1.5mm 
 Coil resistance: 560

Ω ±10% @ 25±5℃ 

 Coil inductance: 240 mH

±15%@1kHz@25℃ 

Wiring terminals of fittings: A – signal +, B- signal – 
Fixing: it is fixed below the throttle body and near the 
crank shaft flywheel 
The fixing cardboards and set bolts need to be fixed 
in the right place.  
曲轴传感器：Crank shaft sensor 
 
3. Fault diagnosis 
Tips: All the following judgments are based on the 
normal operation of the vehicle, wire harness and 
other system components. 
Faults are discovered by the system and 
displayed on the diagnostic instrument:  
Ground fault of the shielding of the signal 
wires in the wire harness 
The magnetic core absorbs too many metal 
dusts; over clearance between sensor and gear 
ring; 
Incorrect relative position or displacement of 
the gear ring to the crank shaft 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

Three. Manifold pressure/temperature sensor 
(MAP/MAT) 
1. Functions and principles: 
The air intake manifold pressure sensor and the 
air intake temperature sensor are combined 
together for the convenience of fixing and 
operation; 
The air intake pressure sensor monitors the air 
intake pressure. Subject to computer calculation, 
it can also indirectly measure the air intake 
quantity, control fuel injection time of the spray 
nozzle, while controlling ignition timing and 
idle speed stability as the engine load signals.  
The ignition switch is turned on, the air intake 
pressure sensor measures the air pressure and corrects 
the engine ignition timing and idle speed.  
Wiring terminals: 
A-Pressure signal 
B- +5V 
C-Temperature signal 
D-Signal position; 
Fixing: it is fixed above the air intake manifold. 
2. Component parameter: 
Pressure scope: 15-102kPa 
Working temperature: -40

 

～

 

105

o

C 

Working voltage: 5.0 ± 0.1 V 
Working current: 12mA (max.) 
Output resistance: < 10 

Ω 

DC load: 30 k

Ω (min.) 51 kΩ (recommended) 

Output function: Eo=Er (0.01059P - 0.10941) 
(where P unit is kPa). 
 
 

Pin 

 

Idle speed voltage 
(V) 

Pin 

 

Idle speed voltage(V) 

A 

1．3 

B 

5 

C 

2．35 

D 

0 

 
 
 
 
 
 
 
 
 

 

Co-relation between the air intake temperature sensor resistance and temperature 

Temperature Resistance 

Temperature 

Resistance 

℃ 

Ω 

℃ 

Ω 

100 

177 

15 

4550 

80 

332 

5 

7280 

60 

667 

-5 

12300 

45 

1188 

-15 

21450 

35 

1802 

-30 

52700 

25 

2796 

-40 

100700 

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 the intake vacuum of the engine; 
Check if the adjusting throttle suffers any leakage;  
Check if the intake and exhaust pipelines are blocked.  
 
 
Four. Cooling fluid temperature sensor 
1. Functions and principles 
The cooling fluid temperature sensor is used to detect the working temperature of the 
engine; ECM will provide the best control scheme for the engine based on different 
temperatures; the cooling fluid temperature sensor measures the engine cooling fluid 
temperature, transfers it into voltage signals for the ECM which then controls the fuel 
injection, ignition timing, cooling fan, idle speed control, water thermostat, etc. according 
to the input signals.  
Thermal resistance of negative temperature coefficient is adopted as the inductance 
component for the cooling fluid temperature sensor.  
Wiring terminal: 1-Signal grounding 2-Temperature signal 
Fixing: the cooling fluid temperature sensor is fixed onto the cooling fluid cycling 
passage behind the engine.