CHERY·A21 SERVICE MANUAL ENGINE EFI SYSTEM
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6
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Check the sensor and actuator joint if it is loosening or bad contact.
Important notice: if the above phenomenon is appeared, you should repair the above the
failure at first otherwise it will influence the later service.
Diagnosis help:1 Confirm there is no engine failure record;
2 Confirm that the failure exists before the customer complaints;
3 Inspect the engine according to the above steps and find nothing wrong;
4 During the service please do not ignore the influence from vehicle
maintenance, cylinder pressure, mechanical ignition timing and fuel
conditions;
5 Replace ECU and carry out test. If the failure is deleted, the failure is in
ECU; if the failure can not be deleted, replace back to the original ECU and
repeat the flow and check and repair it again.
5.2 TYPICAL FAILURE DIAGNOSIS FLOW
1. The engine does not rotate or rotate slowly when it is started
The normal failure component: 1) accumulator; 2) starting motor; 3) cable or ignition
switch; 4) mechanical part of the engine.
The general diagnosis flow:
No. Operating steps Result Follow up steps
Yes Next step
1
Check the voltage value between the two wiring terminals
of the accumulator by multimeter; check if it is around
8-12V when the engine is starting.
No
Replace
accumulator
Yes Next step
2
Put the ignition switch at start position, checking the anode
terminal of starting motor by multimeter and observe the
voltage if it is above 8V.
No
Repair or
replace cable
Yes
Repair or
replace starting
motor
3
Disassemble the starting motor and check its working
conditions. Check if there is open circuit or jammed by
poor lubricating.
No Next step
Yes
Change to
correct
lubricant
4
If the failure is happened in winter time, check if it is
because of the wrong engine lubricant and gearbox oil
causes the big resistance of the starting motor.
No Next step
Yes
Repair the
engine inside
resistance5
Check the mechanical resistance inside of the engine if it is
too big causes the starting motor can not rotate or rotate
slowly.
No
Repeat the
above steps
