Great Wall GW491QE, Руководство по обслуживанию

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EF.1-36
8
．
Unstable idle-speed or even flameout when under load eg. air-conditioner, etc.
S.N. Operation steps
Check
result
Follow-up steps
Yes
Clear the displayed failure
away.
1
Place ignition switch to the ON
”
position. A fault diagnosis instrument may be
used to check whether there’s any record of failure information.
No Next step.
Yes Next step.
2
After a connection of air-conditioner switch, connect a commutator between
ECU and wiring harness, and measure whether there’s a signal input
*
”
between the Pin 40 and Pin 41 air-conditioner switch of ECU.
No
Check and repair the
air-conditioner loop.
Yes Next step.
3
Check whether the pressure of air-conditioner system, the electromagnetic
clutch of compressor, and the air-conditioner pump are under a normal
condition.
No
Repair or change it
Yes Next step.
4
Place ignition switch on the ON
”
position, and check whether respective
voltage on the Pin 4
No Check the control loop.
Yes
Repair or change the
idle-speed actuator
5
Check whether the idle-speed actuator has got stuck or is able to run flexibly
after it has been removed.
No Next step.
Yes Change the ECU
6
Start the engine, and activate the air-conditioner function, and check for some
time whether the idle-speed actuator is working in a normal way.
No
Change the idle-speed
actuator
*The signal of low /high electrical level from Pin 41 may be regarded as an air-conditioner request signal by ECU: ECU is able
to recognize the signal of low electrical level from Pin 41 as an air-conditioner signal requested by vehicle, and the signal from
Pin 41 shall be of high electrical level when A/C switch is OFF. And vice versa.
9
．
Periodically unstable Another self-learning is needed after a power cut to ECU
S.N. Operation steps
Check
result
Follow-up steps
Yes
Clear the displayed failure
away.
1
Place ignition switch to the ON
”
position. A fault diagnosis instrument may be
used to check whether there’s any record of failure information.
No Next step.
Yes Next step.
2
Check whether the passage of air filter is free.
No Change it.
Yes Next step.
3
Check whether the pressure of inlet manifold is within 35kpa and 65kpa while
engine is running at idle-speed.
No
Check and repair air inlet
components or
components leaking air.
Yes 7
4
Perform a flameout process for each cylinder while engine is running at
idle-speed, and observe whether the rotating-speed of engine has some
fluctuation or has been decreased.
No Next step.
Yes Next step.
5
Place ignition switch on the ON
”
position, connect a commutator between
ECU and wiring harness, and check whether respective voltage on the Pin 7
output of absolute-pressure sensor for inlet manifold , Pin 44 output of
air-inlet temperature sensor , Pin 45 output of cooling-fluid temperature
sensor , Pin 28 output of oxygen sensor , Pin 19 electronic ground , Pin
27 ignition switch , and Pin 4 &26 output to the idle-speed actuator of
ECU is normal.
No
Repair or change the
wiring harness
Yes Clean it.
6
Check whether sensing holes on the inlet-manifold pressure sensor and the
air-inlet temperature sensor have been blocked.
No Next step.
Yes Change the fuel
7 Check whether fuel contains water or has deteriorated.
No Next step.
Yes Next step.
8
Check whether the oil injector is able to work in a normal way after it has been
provided with a 12V voltage by accumulator via special connector.
No
Check and repair the oil
injector and its relevant
wiring harness.
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