VSC Vehicle stability control

[Glenn the Dad]

On a 2004 RX 330 I discovered while, cruising above 40 mph, turning slightly to the right, and slightly to the left the VSC light would come on and beep. Then, when turning a little more (but not hard), to the right or left. He would begin breaking until you let your foot off the throttle, and then it would slow naturally. However, when you would begin to reapply the throttle, it would begin breaking again. This creates a very dangerous situation on an acceleration ramp when everybody else is trying to speed up. It is also very dangerous on a deceleration ramp as it brings you down below this necessary speed to make the curve abruptly.

I have spent about eight hours over the last three days researching this, and only coming up with links to turn off the VSC and ABS light on the dash. I have also tried to re-calibrate it using the OBD connector for its auto diagnosis program.  Unfortunately, this also had no effect. It seems as if the sensor is too sensitive to turning. Does anyone know if it would be the TPMS monitoring possibly triggering it or some programming within the ECM module?

any help would be appreciated. Thanks.

[RX400h]

How old is your battery?
Have you reseated the gas cap?

[Glenn the Dad]

On 10/18/2004 at 2:25 AM, Kally said:

HI -

Seeking any help or advice on a scary problem with the automatic Vehicle Stability Control on my LX470 year 2002.

Twice in the last month the loss of traction alarm sounds, lights light up in the main display, and then the left side brakes pump 2 or 3 times. When the VSC engages, it brakes pretty hard, not locking, but Hard on the left side. The whole vehicle then pulls to the left and I have to steer right to keep in my lane.

Both times I was driving about 65 mph on a dry clean freeway with a slight right curve. The first time I was inside a tunnel here in the San Francisco bay area, and it really scared the S*** out of me. Second time, the alarm sounded and I just got ready for some creative driving and it did the same thing. The brakes engage about 5 seconds after the alarm goes off and the whole "experience" lasts about 15 seconds before returning to normal.

I've had the dealer look for the problem and they can't reproduce it. I've really enjoyed the truck for 2 years now with no issues, but this is a new one to me.

Has anyone heard of problems with the VSC or something like this? How can I diagnose or narrow the problem down?

Thanks!

I haven’t found anything yet either but going for new tires(12-17-22) going to check TPMS monitoring and chat with mechanic tomorrow. 

[Glenn the Dad]

Gas cap yes. 
As for the battery I will check it in the morning. 

[Ezra]

I had this problem with my Camry SE one time… it was the ABS speed sensors. Whenever I’d hit the brakes the VSC and ABS light would come on… try having the speed sensors checked they were a cheap ($24 amazon for 2) easy fix on my Camry.. not sure about your Lexus… good luck 

[Glenn the Dad]

On 12/16/2022 at 9:03 PM, Glenn the Dad said:

On a 2004 RX 330 I discovered while, cruising above 40 mph, turning slightly to the right, and slightly to the left the VSC light would come on and beep. Then, when turning a little more (but not hard), to the right or left. He would begin breaking until you let your foot off the throttle, and then it would slow naturally. However, when you would begin to reapply the throttle, it would begin breaking again. This creates a very dangerous situation on an acceleration ramp when everybody else is trying to speed up. It is also very dangerous on a deceleration ramp as it brings you down below this necessary speed to make the curve abruptly.

I have spent about eight hours over the last three days researching this, and only coming up with links to turn off the VSC and ABS light on the dash. I have also tried to re-calibrate it using the OBD connector for its auto diagnosis program.  Unfortunately, this also had no effect. It seems as if the sensor is too sensitive to turning. Does anyone know if it would be the TPMS monitoring possibly triggering it or some programming within the ECM module?

any help would be appreciated. Thanks.

12-23-22

  We replaced the steering rack, left CV axle and the sway arm linkage. We also had alignment done and recalibrated the system. after putting new tires on as well. This was the the cure needed. The play in the steering rack caused the the problem, with the steering angle sensor to be off by up to 40 degrees off.

 Now operates perfectly. 

[Bykfixer]

Wow!! That is crazy!!! Glad you found the issue. The steering sensor being off causes brakes to self-engage? Never would have guessed that was the reason. 

What caused you to check the steering rack? 
 

[Glenn the Dad]

  It was in need of tires. When on the rack I had prearranged for inspection and had mentioned the issue. The mechanic showed me what was happening. Described how the loose components lead to the steering angle sensor being the secondary reaction to the actual problem.

  Having driven it to work A couple days to try to surmise the issue for myself. His explanation made complete sense.

[Guest]

Can you explain clearer because you said it was in need of new tires but that's not the same as loose components. I've had worn out tires before and never recieved a VSC light. The only times(that I recall) that ive gotten the VSC light was when I was skidding in the snow. 

[Bykfixer]

Each time I have tires replaced I do same Glenn. Have the suspension and steering parts checked to ensure my shiney new tires don't wear out premature. 

Whatever the cause was, it still freaks me out the car had a mind of its own to apply the brakes. I'd expect that from a horse but not an automobile. 🥴

[Guest]

22 hours ago, Bykfixer said:

Each time I have tires replaced I do same Glenn. Have the suspension and steering parts checked to ensure my shiney new tires don't wear out premature. 

Whatever the cause was, it still freaks me out the car had a mind of its own to apply the brakes. I'd expect that from a horse but not an automobile. 🥴

Its not as bad as it sounds when the driving brakes are applied. I'm driving with applied brakes because my ABS system needs to be replaced.

Went from 32mpgs to 19mpgs. Actually pretty driveable.

[Glenn the Dad]

The brakes don’t remain on. They self apply at very inopportune times. Such that it makes a situation dangerous.

  For instance, my wife was entering a major highway on an entrance ramp to a major thoroughfare the play in the wheel caused the steering angle sensor to activate the brakes every time she would depress the gas. While trying to accelerate out of the corner as you would expect yourself and the vehicles behind you to do the same. Except out of nowhere someone slams on there brakes a few times. Because the system doesn’t just turn off it remains active for a few seconds after the initial event. The semi behind her, just about ran her over. Or if you have an angry person behind you. You may get shot. So if you think about the number of times, you accelerate out of a corner while driving to work or anywhere, this becomes a very dangerous situation.

[Glenn the Dad]

To answer your previous question the steering rack was worn, allowing 40° play in the steering and the tires worn as well. So imagine turning your steering 1/8 of a turn and it not moving. So we’ve been occasionally just going down a roof that had grooves in. It could sit off the warning sensor but maybe not the brakes. 

[Bykfixer]

Sounds like driving a 1970's F-100 pickup truck. You just steered left a little, then right a little then left then right like an old John Deere tractor. If you do it right you get where you're going but if you just hold the wheel without doing the left/right/left thing you'll find yourself in a roadside ditch. 

But at least the brakes didn't join the fight without an invitation.... 

 

[Glenn the Dad]

YES! 

Love the analogy. That's hilarious.

 

[Bykfixer]

How's the car doing @Glenn the Dad ?

[carlzsdropz]

I've had worn out tires before and never recieved a VSC light. The only times(that I recall) that ive gotten the VSC light was when I was skidding in the snow. 

[jkhbn]

Thanks to this post and the person who posted the reply, I learned a lot.