Hyundai GENESIS COUPE BK 2010 Manual page 800

General Description
The rear heated oxygen sensor is mounted on the rear side of the Catalytic Converter (warm-up catalytic converter) or
in the rear exhaust pipe, which is able to detect catalyst efficiency. The rear heated oxygen sensor (HO2S) produces a
voltage between 0V and 1V. This rear heated oxygen sensor is used to estimate the oxygen storage capability. If a
catalyst has good conversion properties, the oxygen fluctuations are smoothed by the oxygen storage capacity of the
catalyst. If the conversion provided by the catalyst is low due to aging, poisoning or misfiring, then the oxygen
fluctuations are similar to signals from the front oxygen sensor.
DTC Description
Checking output signals from HO2S under detecting condition, if an output signal is below 0.04V for more than
predeterminate time, ECM sets P0157. The MIL(Malfunction Indicator Lamp) will illuminate when the fault remains for 2
consecutive drive cycles
DTC Detecting Condition
Item
DTC Strategy
Enable Conditions
Threshold value
Diagnosis Time
MIL On Condition
Specification
(Reference only)
Test Condition
HO2S Signal at idle after warm-up
Detecting Condition
• Monitor signal voltage
• Battery voltage ≥ 10V
• Engine running ≥ 60 sec
• Engine warm-up state
• The voltage of HO2S(B2/S2) < 0.04V
• Continuous (more than 12.5 sec. failure for every 15
sec.test)
• 2 Driving Cycles
HO2S Voltage(Sensor1)
Signal is commonly switching from rich
to lean more than 3 times in 10 sec.
Possible Cause
• Poor connection
• Short to ground in harness
• HO2S(B2/S2)
• ECM
HO2S Voltage(Sensor2)
Signal is commonly above 0.6V.