Dtc 154-Ego2 Open/Lazy - Kubota WG1605-E3 Diagnostic Manual

WG1605-G-E3,WG1605-L-E3,WG1605-GL-E3, DM
DTC 154-EGO2 Open/Lazy (HO
• Hardware: Heated Exhaust Gas Oxygen Sensor (Post-Catalyst)
• Enabling Conditions: Engine Running
• Set Conditions: HEGO/HO
• Corrective Action(s): Illuminate MIL.
• Emissions related fault
• Possible Causes: Open feed circuit to O
wire, open sensor ground (5 Vrtn1), inoperative sensor
In a post-catalyst configuration the HEGO/HO
measures the oxygen content downstream of the catalyst for two main functions: 1) to compare it to the oxygen
content upstream of the catalyst to determine how efficiently the catalyst is using oxygen to determine its
effectiveness and 2) trim the commanded equivalence ratio target to maximize the catalyst conversion efficiency. The
post-catalyst strategy and diagnostic is only active when the system is in either "CL Active" or "CL + Adapt" control
modes.
Cold or non-responsive is defined as the actual impedance of the sensor heater not reaching the target
impedance.
S2)
2
S cold or non-responsive longer than 120 seconds
2
heater, Open heater ground circuit, Open or shorted to ground O
2
S sensor is a switching-type sensor around stoichiometry that
2
1-161
ECM SYSTEM
signal
2
KiSC issued 12, 2016 A