Help! - Engine Managemt Light

[alamkhan3980]

Hi all,

My car now has the management light on.

It come on whilst I was driving, it is still driving fine, no power loss, no overheating, idles ok.

I have carried out some checks, but the light is still on. I do not have a OBD II reader, so I do not know what else to do.

Any suggestions on what I can try?

I need to get this resolved ASAP, as we have sold my girlfriends car this morning and we need a car.

Thanks.

[Steviewevie]

You really need the code(s) read. If it's still running ok then it is hopefully nothing serious.

There are ways to read the codes without a reader, i.e. here, section 2b, but I have a reader and can meet you part-way if you fancy a drive !

[Guest inicol63]

Take it into Lexus they should do a quick check normally without charge to tell you whats up.

Hope fully it will be some thing minor, maybe a 02 sensor.

Good luck

[alamkhan3980]

I have diagonised the cause of my engine management light to be;

P0161 O2Sensor Heater Circuit Malfunction (Bank #2 Sensor #2)

However, the engine management light does not stay on constantly. When it started last weekend, it was on all day and then when I went to meet Steve it turned off and stayed off for the rest of the night and following day. The light then come on Tuesday and has been on constanlty until today.

Is the usual behaviour when an O2 sensor starts to fail or could the error code be a false reading?

[Asi]

http://www.obd-codes.com/p0161 this may help

[Steviewevie]

The IS300-specific official info on this is here and here.

There are troubleshooting procedures outlined there, also further here and the main one to do is probably testing the resistance of the sensor, providing you have a multimeter,

I don't really know whether this is usual failure, but I guess it's not impossible that it's starting to fail, so it works some of the time and not at other times. The O2 sensor has a heating circuit to enable it to work efficiently, and maybe something is going wrong with this, and some of the time it's warm enough to work ok and at other times not ? Just a guess.

Could also be a loose wire of course but IMHO I think this is less likely unless there's been some recent work done in that area.