Steps For Implementation Of Failure Diagnosis By Engine Symptom; Perform Preliminary Inspection First Before Following The Steps For Implementation Of Failure Diagnosis By Engine Symptom - Chery QQ6 Service Manual

12. Steps for Implementation of Failure Diagnosis by Engine
Symptom
12.1 Perform Preliminary Inspection First before Following the Steps for
Implementation of Failure Diagnosis by Engine Symptom.
(1) Make sure that ECU and failure indicator lamp (or EPC lamp) have no off-normal
phenomenon (excluding the models that have no failure indicator lamp).
(2) Use a failure diagnostic tester to check and make sure no failure information record
exists.
(3) Employ failure diagnostic tester to check that hot idle data from electronic control
system fall within normal scope.
Hot idle speed parameter table:
Name
Air intake temperature
Battery voltage
Temperature of engine coolant
Position of accelerator pedal
Air-fuel ratio control integrator
Ignition advance angle
Outer corner of throttle
Fuel injection time
Engine revolution n
Duty cycle of canister control valve
Self-adapting value of air-fuel ratio
control
Self-adapting value of air-fuel ratio
control
Intake manifold absolute pressure
Voltage of oxygen sensor
Air intake pressure
(4) Validate that the failure effect the owner complained exists and then locate the exact
position of the symptom. Please note that the information provided by the customer is
very important, especially the failure symptoms, occurrence time, position and if any
other failure symptoms occurred before; these information can help technical personnel
rapidly and effectively judge the failure, thus increasing maintenance speed and
improving maintenance quality.
Then check the appearance:
Parameter
20-70℃
12-14V (affected by engine revolution)
℃
80-90 (normal operating temperature)
0%~99.00%
5%-5%
5-10° ( may change with fluctuation of
engine revolution )
0%~99.61%
2-7ms (has a strong relation with engine
revolution)
Expected idle speed ± 50rpm
0%~99.9%
0.95-1.05
120-140
350-650hPa
Quickly fluctuates at 0.1-0.9V