Lexus P0031 HO2S Heater Control Circuit Low Bank 1 Sensor 1

Description

OBD-II Trouble Code Description for P0031 Lexus

HO2S Heater Control Circuit Low

What does this mean?

OBD2 Code P0031 Lexus definition:
A P0031 Lexus DTC (diagnostic trouble code) definition:the O2 sensor (oxygen sensor) located on Bank 1 in front of the catalytic converter. There is also an oxygen sensor behind the converter which is Sensor #2. This O2 sensor #1 may also be refered to as an air/fuel ratio sensor since on some vehicles it is. It detects the amount of oxygen in the exhaust gas compared to the outside air and then vehicle’s computer adjusts the air/fuel ratio going into the engine. The sensor is less effective when the exhaust gas temperature is low, so it includes a heater which is activated to help get better readings from the A/F O2 sensor. Essentially this P0031 Lexus code means that the resistance of the heater circuit is lower than normal. In most cases, that resistance level must fall below 0.8 A to trigger the DTC code. Note, this code is very similar in nature to P0032 Lexus, P0051 Lexus, and P0052 Lexus

Symptoms

Possible sumptoms of OBD code P0031 Lexus
Most likely you’ll not notice any symptoms other than the MIL (malfunction indicator lamp, a.k.a. the check engine light) will illuminate.

Causes

Possible causes of OBD code P0031 Lexus
A P0031 Lexus DTC trouble code may be caused by one or more of the following: A short or open in the heater circuit in the sensor A failed O2 sensor heater Wiring/connectors broken/frayed leading to sensor and/or relay Failed PCM/ECM

Possible Solutions

To fix a P0031 Lexus DTC code, you’ll need to do a proper diagnosis. To do that, you’ll want to inspect the wiring and connectors leading to the sensor. Also if equipped with a heater relay and fuse, you’ll want to check those as well. Use a digital volt ohm meter to: check for 12 volts at the heater circuit feed (hint: unplug the sensor and check at the wiring connector to do this measurement) check the ground circuit for continuity measure the resistance of the heater circuit (done on the sensor itself) measure the resistance and voltage of the wiring Refer to a service manual for the correct specifications (volts, ohms) for your vehicle. On some Toyota vehicles this code is triggered when the resistance of the heater circuit is below 0.8 A. With that said, a common fix for this DTC is to replace the air/fuel (O2 oxygen) sensor #1 on bank 1. Please keep in mind that OEM (original equipment) replacement sensors are recommended (from the dealer). Aftermarket sensors can be less reliable and of poorer quality (not always, but more often). There’s also a chance that replacement parts for the P0031 Lexus code may also fall under a federal emissions warranty (check with your dealer to see if it’s covered).

Related Codes

P0010 Lexus P0011 Lexus P0012 Lexus P0021 Lexus P0022 Lexus


The OBD2 Code Information Be Applicable For Lexus:

2013 Lexus RX 450h F Sport,2013 Lexus RX 450h,2013 Lexus RX 350 F Sport,2013 Lexus RX 350,2013 Lexus LX 570,2013 Lexus LS EU-Version,2013 Lexus LS 600h L,2013 Lexus LS 460 F Sport,2013 Lexus LS 460,2013 Lexus LF-NX Concept,2013 Lexus GS 450h F Sport,2013 Lexus GS 450h,2013 Lexus GS 350 F Sport,2013 Lexus GS 350,2013 Lexus GS 250,2013 Lexus ES 300h,2013 Lexus ES350,2012 Lexus LF-LC Concept,2012 Lexus LF-CC Concept,2011 Lexus LFA,2011 Lexus LF-Gh Concept,2011 Lexus IS 350 F Sport,2011 Lexus IS 350,2011 Lexus CT 200h,2010 Lexus SC 430,2010 Lexus RX 450h,2010 Lexus RX 350,2010 Lexus LS 600h,2010 Lexus LS 460 Sport,2010 Lexus LS 460 L,2010 Lexus IS250C,2010 Lexus HS 250h,2010 Lexus GX 460,2010 Lexus GS 460,2010 Lexus GS 450h,2010 Lexus GS 350,2010 Lexus ES 350,2009 Lexus SC430,2009 Lexus LS,2009 Lexus LS460,2009 Lexus LF-Ch,2009 Lexus IS 350,2009 Lexus GX 470,2009 Lexus GS 460,2009 Lexus GS 450h,2009 Lexus GS 350,2008 Lexus LX 570,2008 Lexus LS 600h L,2007 Lexus LS,2007 Lexus LF,2006 Lexus SC,2006 Lexus IS350,2006 Lexus GS,2005 Lexus RX400h,2005 Lexus LFA Concept,2005 Lexus ES330,2004 Lexus RX330,2004 Lexus LS430

 

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