Newbie, so take it easy if I haven't perfected the search techniques. Check Engine light on. Traction Control light indicates OFF (and can't be turned back on w/o DTC reset, then indicates again in 10 mins driving). Code Reader says: P0037 HO2S Bank 1 Sensor 2. Obviously (?) one should have nothing to do with the other. Is this a known GS300 error? Is the ABS / traction system really off or just wrongly flagged by the computer? The G1S2 fault is real - open circuit heater. Thanks.

 

What you are reading is the Engine DTC's. You need to check the ABS/Traction Control module for DTC's as well. Get that done and you should have you answer.

You need a scan tool that does more then just Generic OBDII to scan the ABS/Trac Ctrl module.

 

Very known DTC for GS300. Go ahead and change the 02 Sensor. There is a thread about this on 02 sensors.

 

Many thanks for the confirmation of Lexus software error. I am assuming that it isn't simply a wiring error at the warning light because the TC switch can't switch the light on / off. Anyway, sensor changed, check engine light reset, and bogus traction control light didn't come back on. Does this nonsense happen with all four O2 sensors? Is it confined to heater failures like the P0037, or the sensor element itself?