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Secondary HO2S Monitor

WARNING: This page is about a different car, the 2006 Suzuki XL-7. However, it is still accessible from the selected car via links, so may be relevant.

Operation 

SECONDARY HO2S MONITOR OPERATION

DTCs P0139 (Bank 1) / P0159 (Bank 2)
Monitor execution Once per driving cycle
Sensors / components OK MAF, TP, ECT, Primary / Secondary HO2S, Primary / Secondary HO2S heater
Monitoring Duration  
SECONDARY HO2S MONITOR OPERATION

DTCs P2A01 (Bank 1) / P2A04 (Bank 2)
Monitor execution Once per driving cycle
Sensors / components OK heater
Monitoring Duration 120 s

Enable conditions 

SECONDARY HO2S MONITOR ENABLE CONDITIONS

Parameter Minimum Maximum
P0139, P0159 
Dual feed back mode On  
F/C mode duration time 3.0 s  
ECT   110 (230) °C (°F)
Misfire No DTC  
EGR system monitor No DTC  
Fuel system monitor No DTC  
P2A01, P2A04 
F/C mode duration time 3.0 s  
ECT   110 (230) °C (°F)
Dual F/B mode time 120 s  
IAT -8 (17.6) °C (°F)  
Barometric pressure 74.5 kPa  
Misfire No DTC
EGR system monitor No DTC
Fuel system monitor No DTC

Typical malfunction thresholds 

SECONDARY HO2S MONITOR TYPICAL MALFUNCTION THRESHOLDS

P0139, P0159 
HO2S switch time from 0.5 V to 0.2 V > 2 s
P2A01, P2A04 
HO2S max voltage - min voltage < 0.3 V
HO2S min voltage > 0.2 V