Louczar1

Mt wifes 2015 has been a great vehicle for us so far. There is a very intermittent issue with traction control turninig on..while stopped. She has experienced the issue 2 or 3x. It happened to me once a year ago and again last week. When it happens, I only have to put the vehicle in park and then back in drive to clear it. I dont like taking anything so intermittent for anyone to try to look at it.

mcomer

Traction Control is On by default every time we start our cars.
Are you describing the Traction Control Off as when we press the button Trac Off?
Normally reserved for rocking out of mud or snow...
Or are you describing the Trac light that illuminates when you are really spinning
the tires and the system is fighting the wheel spin

Clutchless

It could still store codes for this problem even if intermittent.

Louczar1

The exact scenario is I am stopped at a light and the traction control light turns on in the instrument panel. If we try to go when the light turns green, the car will be very slow. putting the car in park and back into drive solves the issue.

RX in NC

How old is your battery? Failing batteries can cause very unusual transmission issues. Today's vehicles are essentially rolling computers.

Louczar1

It was replaced when we bought the vehicle for her...it was a CPO. I would expect this (and other issues) to happen more often than only a few times in the last couple of years.

Clutchless

Don't let your expectations interfere with the analysis of what may be the problem. We are just trying to respond to your request for assistance.

I see 2 ways to initially pursue this problem:

1) Get your battery tested before pursuing other areas of potential fault. Any battery can fail at any time.
The chain auto parts stores will check your battery for free.

2) When did you buy it? How many miles are on it? Is the CPO warranty still in effect? If so, then just go back to the Lexus dealer.

Louczar1

We bought it a little over 3 years ago. the CPO warranty is expired. I agree with you that we should always start with the basics...including the battery. The post was mostly to see if anyone else had seen this issue on their own RX.

Non

I think you may be unintentionally engaging the "Hill-start assist" system, you may not even realize that the car has it. It's designed to hold the brakes when you release the brake pedal for a few seconds, in order to prevent the car from rolling back.

Why don't you test it. Next time you drive the wife's car, engage the "Hill-start assist" system on purpose, just to see if the symptoms are the same.

Check page 276 of your owners manual for more info.

Louczar1

Not a bad suggestion. It is the traction control light that comes on the dash. I am very familiar with that light on our cars :-)

Louczar1

I have been able to duplicate the issue 2x in the few weeks. While stopped at a red light, I was adjusting my position in my seat and had pushed a little harder on the brake while moving my butt and it came on. The same scenario happened once more when I was adjusting my seating position while stopped. It is a 1 out of 20 or so in attempts to duplicate the issue.

djovaniii

yeap, that sounds like the hill assist.
If you press the brake hard and keep it, you activate the hill assist, and indeed that flashes the traction control light.

RX in NC

Agreed. Our 2015 RX350 is my wife's car that I rarely drive. Whenever I do, I have to remember to go lighter on the brake pedal so I will not continually activate the hill assist feature. It took me quite awhile to learn how to quit doing this.