Chery A15. Manual - part 118

 

The thermo-sensitive resistance is made of a kind of semiconducting material with negative 
temperature coefficient, where its resistance will sharply decrease as the temperature 
increases. 

 

5. FUEL METER   

The operation of the fuel meter is basically the same as the water temperature meter. It is also 
the cross coil type of indicator needle meter. See figure below (Illustration-5)—the fuel meter 
is located at right of the figure. 

                                                                                                   

 
 
 
 

 

 
 

Fuel meter (Illustration-5) 

When the float is moving along with the fuel level in the fuel tank, the sliding contact linked 
with the float staff will respond accordingly so as to change the value of the thick-film 
resistance. When the fuel tank is full, the value of the thick-film resistance will be the 
minimum and the current of the cross coil will be the maximum. The indicator needle of the 
fuel meter points at the maximum scale F. On the contrary, when the fuel in the tank is 
exhausted, the value of thick-film resistance will be the maximum, and the indicator needle 
deflexion value of the fuel meter points being the minimum scale E. 

The relationship between fuel quantity and resistance is indicated in the table below. 

The relationship between fuel quantity and resistance 

Float position 

Capacity (L) 

Resistance (Ω) 

Empty  

0 

283 

Half full 

30 

89 

Full 55  36 

 

 

 

 

FAULT DIAGNOSIS AND TROUBLESHOOTING 

 

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Components 

Malfunction 

symptoms 

Malfunction 

reasons 

Malfunction diagnosis 

and troubleshooting 

Remarks

The 

speedometer 

does not 

function or 

have an 

excessive 

error. 

The 

speedometer 

does not 

function or 

there is a large 

error between 

the indicated 

speed and the 

actual speed. 

(1) The Hall 
Speed Sensor of 
speedometer. 
(2) The indicator 
needle of 
speedometer is 
jammed. 
(3) Output shaft 
driving gear of 
gearbox is 
seriously worn 
out or the gear’s 
engagement 
clearance is 
excessive. 
(4) The 
speedometer is 
damaged. 
(5) The engine is 
damaged. 
(6) The 
connecting circuit 
is faulty. 

(1) If the speedometer does 
not function, firstly inspect 
the engagement of Hall 
Speed Sensor and the drive 
gear to verify that there is 
any malfunction. If 
everything is normal, then 
remove and inspect the 
speedometer. 
(2) In the case of only 
inaccurate indication 
malfunction, it is caused 
usually by the damage of 
the interior part of the 
meter. 
(3) Inspect the link 
between the speed signal 
and the ECU, and the 
signal wire between engine 
and instrument. 

 

The water 

temperature 

meter does 

not function. 

The indicator 

needle of 

water 

temperature 

meter does 

not function 

after engine 

starting. 

(1) The water 
temperature meter 
is damaged. 
(2) The water 
temperature 
sensor is 
ineffective. 
(3) The circuit of 
water temperature 
meter is open. 
(4) The voltage 
regulator is 
damaged. 
(5) The ECU is 
damaged. 

(1) Open the engine bonnet 
and pull out the connector 
of the water temperature 
sensor. Inspect whether the 
resistance of water 
temperature sensor is 
normal; if it is normal, 
inspect the signal from 
sensor to the ECU, and 
signal from the ECU to 
instrument. 
(2) If the above circuits are 
normal, connect it to the 
connector of combination 
instrument and turn on the 
ignition switch. Inspect to 
see whether voltage 
appears at the yellow/red 
wires of water temperature 
sensor connector. If 
voltage appears, it 
indicates that the water 
temperature sensor is 
damaged; if there is no 
voltage, it indicates that 

 

 

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water temperature meter or 
voltage regulator is faulty. 
(3) Remove the instrument 
panel and maintain the 
normal connection of the 
wiring harness. Connect a 
multimeter between the 
output terminal 1 of 
voltage regulator positive 
grid and the grounding 
terminal 2 to measure the 
voltage. If the voltage is 
higher than 10.5V or lower 
than 9.5V, it indicates that 
the voltage regulator is 
faulty; Otherwise it 
indicates that water 
temperature meter is faulty 
itself. 

The fuel 

meter does 

not function 

The indicator 

needle does 

not move after 

ignition 

switch is 

turned on. 

(1) The fuel meter 
is damaged. 
(2) The fuel meter 
sensor is 
ineffective. 
(3) The circuit of 
fuel meter is 
open. 
(4) The voltage 
regulator is 
damaged. 
(5) There is no 
fuel in the fuel 
tank. 

(1)Verify that there is 
gasoline in the tank. 
(2)Turn on the ignition 
switch and verify that the 
water temperature gauge 
functions properly. If the 
water temperature gauge 
functions properly, it 
indicates that the voltage 
regulator of the combined 
instrumentation functions 
properly. 
(3) Disconnect the plug of 
the sensor of the fuel 
meter, inspect with 
multimeter that there is 
electricity in the 
purple/black wire, and then 
inspect the grounds of the 
brown wire and the body. 
If there is electricity in the 
purple/ black wire and the 
brown wire is normal, 
which indicates that there 
is malfunction in the fuel 
meter sensor, and it must 
be replaced. 
(4) If there is no electricity 
in the purple/black wire, 
then verify that the circuit 
between  purple/black wire 

See 

circuitry 

diagram of 

the fuel 

meter 

 

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of the plug of the fuel 
meter sensor, and the 21# 
socket of the connector of 
the combined 
instrumentation is open, 
the route of the circuit is: 
purple /black wire of the 
plug of the fuel meter 
sensor→ the 3# socket of 
the connector M of the 
relay plate → the #12 
socket of the connect U1 
of the relay plate → the 
brown wire → the #21 
socket of the connector of 
the combined 
instrumentation. 
(5) If the circuit is on and 
the brown wire is normal, 
then there is malfunction 
in the fuel meter. 

Oil warning 

lamp always 

on 

The warning 

lamp for 

engine oil 

pressure is 

always on 

while driving. 

(1) Malfunction 
of low pressure 
switch (30KPa 
switch). 
(2) Low pressure 
switch circuit is 
short. 
(3) Malfunction 
of high pressure 
switch (180kPa 
switch). 
(4) High-pressure 
switch circuit is 
open. 
(5) Pressure in the 
lubricating oil 
circulation can 
not reach the 
specified 
requirement. 
 
 
 
 
 
 
 
 
 

Firstly identify whether the 

lubricating system or 

warning system is faulty. 
This is normally done by 

measuring the oil pressure 

to diagnose the 

malfunction. 

(1) When connecting the 
positive grid of the battery 
and the low-pressure 
switch with a diode testing 
light, the latter will be 
lighted. Start up the engine 
and increase the speed 
slowly. When the pressure 
reaches 15-45KPa, the 
diode-testing light should 
be off. Otherwise it 
indicates that the 
low-pressure switch is 
faulty; run the engine at 
idle speed, with oil 
pressure higher than 
45KPa, the light-emitting 
diode should be off. If the 
pressure is lower than 
15KPa, it indicates that the 
lubricating system is 
faulty. 

 

 

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