I own a 1993 Ls 400 with above problems. While driving the trac off light and check engine light come on and the traction system is off. Pushing the traction control button will do nothing and I tested the traction and it is indeed off. I reset the ecu (disconnected the negative battery cable) and problem goes away for 200-400 miles. When I do reset the ecu, the traction and cel are off, and the trac system works perfectly. This was fine in the summer, but now that winter is here, won't be much fun getting out to reset the ecu every 200-400 miles to get traction for these new england winters. Any ideas?

thanks

Mark

 

is there that you don't want to take the car into a Lexus dealer and have it fixed?

Then buy the shop manuals and follow the diagnostic procedure to see why the ECU is saying something about the engine "system" is failing.

 

Yes Willard, there is a reason why I don't take it to the Lexus shop to have this problem fixed. I see you have 3 lexi in your garage. I have but one, and it cost me my last 12k cash to buy and I was hopeing the reliabilty would be perfect until I saved up some cash for maintenence. I posted this hopeing this was common problem and there was an easy solution--such as a sensor I could buy and install myself as I am very mechanical. I can fix most things myself, but electronic computer controlled engine functions is where I draw the line.

 

The water is actually quite warm over here....

No, really, I understand your reluctance to dig into the unknown. But in this case we are not talking about the unknowable. If you can't afford the $200 for the shop manuals do you live nearby so I can loan you mine.

Actually I may have an early set some hwere is you want me to look around.

 

Every car I have owned has a manual way of retreving the codes and the manual tells you what each one means.
For ex. on my stealth you need a analog voltmeter to connect the positive and the ground to a diag connector under the dash.The amount of pulses the voltmeter reads determines the problem.In this case my problem was a code 14 which was a TPS sensor.
On the LS there is also a diag connector under the dash and by the circuit breaker which trips non working components in the car.
Now somone needs to post the meaning of each flashing code and how to retrieve it.(please post the info from the manaul)

 

I had the same problem with my 92 Ls, I found out that the codes for that specific problem could be hectic. I took it in to my mechanic and he found after $800 of searching for the problem that it was as simple as replacing the oxygen sensors. Our car has 3 of them, I recomend replacing them all and seeing how that works. It's the cheapest route to go first or else you'll have to do what i did, that is the process of elimination. Hope this helped, and let me know if it worked.

 

Most of Lexus dealers I experienced will diagnose and figure out most of your problems for free. It's the actual repair that cost money, so it might be easier to just take it in and see what's happening. Then DYI if you can later on.

 

Where are you doc?
I wanna know how to retrieve my own codes and their meaning.

 

I had a similar problem with my '92 LS
sometimes when i drove the traction and check engine light would go on, but it would go away when I shut the car off
Then closer to the winter the engine light and traction went on and would never go away unless i reset the ECU, but it would always come back, it used to drive me crazy.
Then I went to my mechanic and they told me that one of the sensors were bad and had to be replaced with the dealer item, something like $200 plus work, but before they did that they suggested cleaning it, b/c the connections were dirty, and thats exactly what they did. Ever since that time, which has been about a year, I havent had any problems.
My suggestion is to check the sensors and try cleaning them, If u can do it yourself, try or go to a mechanic. The whole check up and cleaning didnt cost much. I dont remember how much, but definitely less than $100.

 

Under the dash, above the left knee there is a small round box with a cap. Open the cap, using a paper clip, stick in the ports that say E1 and TE1, turn the ignition on do not start the engine. Count the no. of flash on the check engine light. Notice the pause between the flashes. code 25 mean 2 fast flash pause then 5 fast flashes. If there are more codes there will be a pause between the codes too.

Call 800-908-6968 (Carson Toyota) ask for Steve Ganz (he's a forum member) or Gordon to order the repair manual. The manual will tell what to trouble shoot on the code.

I have my 93 SC400 manual and I think the trouble code are the same on all Lexus. If you don't have the manual yet, post the code and I'll try to help out.

You may need to change your Main O2 sensors.

 

Thanks VQT!

 

 

I have the same exact problem today I was able to correct it using your method. Thanks!!!!! Not going to worry about winter. Car is stored during those months.