Traction Control Lit Up 91 Ls 400

[molod100]

Hi folks!

Please help with advise! I have '91 LS400.

"TRAC" light goes on after driving for about a mile and stays on.

Can it damage the traction control system if I am taking my car on a road trip for about 2K miles?

What are the options and solutions? Will appreciate as much details and help!..

Thanks for your help!!!

My best regards to all you LEXUS LOVERS! :)

[pachocco1]

troubles1.pdfYou might try resetting your ECU. ( Fuse or Bat. Cable)

On the attached matrix it indicates an ECU malfunction.

[gazhalim]

I'm having the same issues. When I have my car in ACC though, the TRAC light will go on or off, depending if I have the button pushed in. But when I start the car, the light stays on indefinitely...

[wwest]

First, the traction control as implemented on the early LS series is worse than useless. I have found myself remembering to turn it off each and every time I start the car. My 92 will soon be at 100k miles.

Each time I have had the Trac diagnostic come on a complete brake fluid flush has solved the problem. But if you have a dealer do it be sure they know of the additional fluid bleed valves on these earlier models vs the newer LS. Especially the one at the Trac pump/accumulator.

[molod100]

Folks,

THANKS EVERYONE !!!!!

I will post the results once fixed - don't know when it'll be done thought.....

[gazhalim]

let me know what happens...

[molod100]

let me know what happens...

←

The problem is gone on it's own - the season is over :)

As odd as it seems, the trac light goes on only in the snowy season...

I had it a couple times last year, but it was much worse this year.

The light stopped go on after well into hot summer season - I guess as someone mentioned in one of the forum postings here, it has something to do with one of the sensors.

Later...

[1990_LS400]

Check the TRAC error code.

My symptom was when it was cold the TRAC will be ON, if I go for an automatic car wash for 5 minutes, then it become normal (i.e. OFF), so it was temperature related. After checking the error code, it was the relay. I checked the circuit diagram of the relay and tested with 12 volt DC, I heard the click sound. So this told me that the solenoid was working, but the ON-OFF contact is not good (i.e. contact problem). Therefore I opened up the relay, sanded the contact and bent the arm a little to make sure it contacts when 12 volt DC is supplied. That work for me so far one year already, save me $100 for the relay.

let me know what happens...

←

The problem is gone on it's own - the season is over :)

As odd as it seems, the trac light goes on only in the snowy season...

I had it a couple times last year, but it was much worse this year.

The light stopped go on after well into hot summer season - I guess as someone mentioned in one of the forum postings here, it has something to do with one of the sensors.

Later...

[fencera]

Check the TRAC error code.

My symptom was when it was cold the TRAC will be ON, if I go for an automatic car wash for 5 minutes, then it become normal (i.e. OFF), so it was temperature related. After checking the error code, it was the relay. I checked the circuit diagram of the relay and tested with 12 volt DC, I heard the click sound. So this told me that the solenoid was working, but the ON-OFF contact is not good (i.e. contact problem). Therefore I opened up the relay, sanded the contact and bent the arm a little to make sure it contacts when 12 volt DC is supplied. That work for me so far one year already, save me $100 for the relay.

let me know what happens...

←

The problem is gone on it's own - the season is over :)

As odd as it seems, the trac light goes on only in the snowy season...

I had it a couple times last year, but it was much worse this year.

The light stopped go on after well into hot summer season - I guess as someone mentioned in one of the forum postings here, it has something to do with one of the sensors.

Later...

This question may not be relevant, but is the relay you are talking about the one that is on the throttle body next to the throttle position sensor? If it is, how did you reinstall it? I keep getting a click under the hood ever since I stupidly removed both the TPS and the Traction control related sensor next to it.

Thanks!

[insurancebasis]

Sir, I have recently purchased a used Lexus with 275,000 miles. Beautiful car, but it seems to be having problems with similar simtoms of a Catlyetic Converter, it is a CA car, but it isn't overheating. It is like I am trying to accelerate with the brake applied. It may be something with the traction control, but when I turn the traction control switch off it gets even worse, I had a hard time just backing it back into the driveway. Please reply.