DTC P0140-00: Ho2S Circuit No Activity Detected: Notes

DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0140:00	HO2S circuit no activity detected
DETECTION CONDITION	The PCM monitors the input voltage from the HO2S when the following conditions are met. Under the following monitoring conditions, if the input voltage from the HO2S does not exceed 0.75 V even though the short term fuel trim is controlled up to 10 % for specified period, the PCM determines that the HO2S circuit is not activated. MONITORING CONDITIONS Drive Mode 03 (Variable Valve Timing, A/F Sensor Heater, HO2S Heater, A/F Sensor, HO2S and TWC Repair Verification Drive Mode) Estimated temperature of the zirconia element inside the HO2S above 450°C {842°F} Diagnostic support note This is an intermittent monitor (A/F sensor, HO2S). The check engine light illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM. PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle. FREEZE FRAME DATA (Mode 2)/Snapshot data is available. The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION	-
POSSIBLE CAUSE	Erratic signal from HO2S HO2S loose Exhaust system leakage HO2S connector or terminals malfunction HO2S heater malfunction Short to ground in wiring harness between HO2S terminal A and PCM terminal 2AI PCM connector or terminals malfunction Open circuit in wiring harness between HO2S terminal A and PCM terminal 2AI HO2S malfunction HO2S deterioration Engine malfunction Insufficient engine compression Engine coolant leakage to combustion chamber PCM malfunction

CAUTION:

Verify the malfunction symptom according to not only the PID value but also the symptom troubleshooting.

RELATED PIDS

Monitor item (Definition)	Unit/Condition	Condition/Specification (Reference)
VSS	KPH, MPH	Displays the vehicle speed
RPM	RPM	Displays the engine speed
O2S12	V	Idle (after warm up): 0-1.0 V Deceleration fuel cut (accelerator pedal released from engine speed of 4,000 rpm or more): approx. 0 V