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.