Dongfeng Sokon; C Series, Руководство по ремонту и обслуживанию

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Fault Symptom & Judgment Method
Fault Symptom: Poor Acceleration
General Reason: Human-made fault
维修注意事项：
Maintenance Notice: Pay attention to the installation position.
Brief Measurement Method
：
(Demount the tie-in) make the digital multimeter on the ohm gear, two tips connect with stitch 1#,2#of sensor
separately, under normal temperature the resistance is 2k
Ω
土
20%. Tow tips connect with stitch 1#,3# separately,
rotate throttle, its resistance change in a linear relation way while opening throttle, but the stitch 2#,3# in a
opposite situation.
Note: pay attention to the resistance value to see if there is a bigger leap while observing the change of
resistance value.
3
．
Knock meter
1
）
Brief Charge & Stitch
2
） Working Principle
The knock sensor is an accelerator sensor by vibration, which is installed on the cylinder body of the engine.
One knock sensor or more than one knock sensor can be installed on the cylinder block. The sensitive element of
the sensor is a piezoelectricity element. The vibration will pass to the piezoelectric crystal through the
quality
block
inside the sensor. Because of the pressure caused by the vibration of the quality block, the piezoelectric
crystal will produce voltage on the two polar faces and convert the vibration signal into alternating voltage signal
to output. Because the frequency of the vibration signal caused by the engine knock is much higher than the
normal vibration signal, the ECU can distinguish the knock signal or no-knock signal after processing.
3 ） Technical Specification
4 ） Fault Symptom & Judgment
Value
Scope
least typical most
Unit
resistance(stitch 1-2) 1.6 2.0 2.4 k Ω
slide arm protect resistance
(sldie arm in the zero,stitch 2-3)
710 1380 Ω
running temperature － 40 130 ℃
voltage of power 5 V
the voltage ratio of right electrode end
position
0.04 0.093 U
p
/U
s
the voltage ratio of left electrode end
position
0.873 0.960 U
p
/U
s