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Secondary HO2S Circuit 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 CIRCUIT MONITOR OPERATION

DTCs P0137 (for bank 1) / P0157 (for bank 2)
Monitor execution Continuous
Sensors / components OK IAT, ECT, MAF, TP, Barometric pressure, Primary / Secondary HO2S, Secondary HO2S heater
Monitoring Duration 30 s
SECONDARY HO2S CIRCUIT MONITOR OPERATION

DTCs P0138 (for bank 1) / P0158 (for bank 2)
Monitor execution Continuous
Sensors / components OK Secondary HO2S heater
Monitoring Duration 3 s

Enable conditions 

SECONDARY HO2S CIRCUIT MONITOR ENABLE CONDITIONS

Parameter Minimum Maximum
P0137, P0157 
Fuel feedback mode On  
Dual feedback mode On  
ECT   110 (230) °C (°F)
IAT -8 (17.6) °C (°F)  
Barometric pressure 74.5 kPa  
Secondary HO2S heater operation time 24 s  
Misfire No DTC
EGR system monitor No DTC
Fuel system monitor No DTC
P0138, P0158 
Battery voltage 11 V 16 V

Typical malfunction thresholds 

SECONDARY HO2S CIRCUIT MONITOR TYPICAL MALFUNCTION THRESHOLDS

P0137, P0157 
Pull-up voltage ≥ 4.5 V
HO2S voltage < 0.05 V
P0138, P0158 
HO2S voltage > 1.2 V