Ive searched but couldn't come up with a definite answer.
well when i bought the sc400 (1992) the cel was off and about half way home 100miles into the trip the cel popped on and trac off light did too. skip forward a few months and winter hit so car was parked for a month with battery dis connected my work car was being used by my boss for a few days so i drove the lexus for the week in the good weather and dry main roads but side roads were still covered in snow. well i drove it for about 50 miles through out the week and the traction control worked fine the whole time until my cel popped on around the 50 mile range and then it quit working why is that and how cn i fix it?
i can find out what is making the cel pop on and can post the cel codes.
im thinking its a o2
the car has 131k miles and timing belt replaced at 100k and all other service done.

 

no help here? ahh i know there are plenty of educated people here

 

Well I'm new but I'll tell you the experience I'm having and maybe it will help you or someone can even chime in on my problem. About two weeks ago I was driving home from work and my trac off, abs, and trac light came on. About 30 seconds later they went off. It happened about three days later it happened again. Three days after that it happened again but then the needles in my gauges died briefly and then came back on. Another two days after that everything died and the car started to feel like it was out of gas. So I figure I have an electrical problem that goes in and out. The lights are coming on because the ECU is getting messed with because of low voltage. So I check my voltage across the battery...12.8V...start the car...12.0V. Dammit I figure I have a bad alternator, shut it down go back into work, come out a little later and start it again...14.4V. Now I'm lost...I take some leads, run it from the battery to inside my car so I can have real drive time voltage to figure out what's going on. Turns out like every second or third day my car will not just jump right up to 14.4, but once it warms up to temp the voltage will go from 12 to 14.4. So my conclusion is the alternator is good but either my regulator is bad or my belt is not gripping right in the cold and the day my battery died driving to work I was bumping my stereo and had the heater on blast. So my reccomendation the you is to get a voltmeter out and start there because your voltage might be doing the same thing as mine. I ordered this to track my voltage future http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWNX%3AIT

 

02 sensor will turn on your check engine light but your check engine light turning on will not disable your traction control.

traction control light will turn on when you have issues with your ABS (even if that light doesnt turn on), or your traction control system.

scan the car for the codes and go from there. there is no magic in all this. its either the hardware, the service, or the wiring that causes faults. eliminate problems in the most common sense way and try things that are most cost-effective/least expensive first.

 

i got the same probably as u man
exactly the same
and couldnt figure it out yet lol

 

Does anything turn dim when you turn on the indicators or when you apply the brakes?
if so it might be this
https://www.clublexus.com/forums/sc-400-300/755-ghosts-in-my-electrical-system.html

is an ongoing problem on sc

mine wouldnt even idle right after playing with the negative terminal and with you taking out the battery this might be the problemw