P0031 - Oxygen sensor heater control ciruit (Bank1 Sensor 1)
DTC P0031 is set when heater current of 0.2 amps or less is present when heater operates with +B at greater than 10.5 volts and less than 11.5 volts (one trip detection logic) or heater current of 0.25 amps or less when heater operates with +B at greater than 11.5 volts (one trip detection logic).
Possible causes are:
l Open or short in heater circuit of heated oxygen sensor.
L Faulty heated oxygen sensor heater.
L Faulty relay.
L Faulty ECM.
If the sensor is bad, which seems to be the case, it has to be replaced to rectify the fault.
Sunday, November 25th, 2012 AT 9:33 PM