Kubota WG1605-E3, Руководство по диагностике

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ECM SYSTEM
WG1605-G-E3,WG1605-L-E3,WG1605-GL-E3, DM
1-179
(12) Knock Sensor (DTC 326, 327)
DTC 326-Knock 1 Excessive or Erratic Signal
• Hardware: Knock sensor #1
• Enabling Conditions: Key On, Engine On
• Set Conditions: Knock sensor 1 voltage above 2.00 V with MAP less than 62 kPa [abs] (0.63 kgf/cm
2
, 9 psia) and
knock retard is a maximum retard value for longer than 3 seconds.
• Corrective Action(s): Illuminate MIL
• Emissions related fault
• Possible Causes: Internal engine damage causing audible noise, knock sensor signal wire routed too close to
spark plug wire, bad sensor, bad ECM
The knock sensor is used to detect detonation through mechanical vibration in the engine block and/or cylinder
heads and provide feedback for the ignition system to retard spark to reduce knock intensity. The knock sensor is
used to protect the engine from damage that can be caused from detonation or knock based on fixed spark advance.
This fault sets if the signal from knock sensor 1 is higher than expected for low load operation as defined in
calibration. If this fault sets, spark is lowered by the amount defined in calibration for Faulted KNK Retard.
DTC 327-Knock 1 Sensor Open or Not Present
• Hardware: Knock sensor #1
• Enabling Conditions: Key On, Engine On
• Set Conditions: Knock sensor 1 signal below 0.005 V, rpm above 2000 min
-1
(rpm) and MAP above 83 kPa [abs]
(0.84 kgf/cm
2
, 12 psia) for longer than 3 seconds.
• Corrective Action(s): Illuminate MIL
• Emissions related fault
• Possible Causes: Knock sensor open internally, signal circuit open or shorted to ground or bad ECM
The knock sensor is used to detect detonation through mechanical vibration in the engine block and/or cylinder
heads and provide feedback for the ignition system to retard spark to reduce knock intensity. In most applications the
knock sensor is used to protect the engine from damage that can be caused from detonation or knock based on fixed
spark advance. In other applications, the knock sensor is used to optimize spark advance and "learn" between spark
tables based on fuel quality.
This fault sets if the signal from knock sensor 1 is lower than expected for higher speed and load operation as
defined in calibration. If this fault sets, spark is lowered by the amount defined in calibration for Faulted KNK Retard.
KiSC issued 12, 2016 A