I may have your solution.
I have an 04 limited V6 with 202,000 miles
I've been struggling with this exact same issue for months. No Check Engine light, all the same lights on as your rig and the horrible BEEEEEEEEEEEEP that comes on once in a while to join in the fun with the dash lights.
I've read thread after thread. I was pretty much convinced I needed the $1800 all in one ABS/master cylinder/pump/reservoir... and I was not to stoked on it.
Then I found a thread on another forum..possibly a lexus forum? I can't remember I've read so many.
I fixed it!!!
Here is exactly what I did to solve it.
Go and find yourself a paperclip. A larger gauge one if possible.
Next.. unplug your battery cables. I unhooked both and then went into the car and turned on the headlights to make sure any power in the system was drained. Then I waited 10 minutes to really make sure.
Next... hook the battery cables back up and make sure they're super snug. Through reading and personal experience I've discovered that Toyota's are super sensitive and get confused easily. There are a lot or reasons for these lights coming on and some of them will throw codes completely unrelated. Some won't throw codes at all. A weak battery, loose battery cables, low brake fluid, bad oxygen sensor, dirty MAF, seized brake caliper, bad wheel bearing, low tire pressure, brake pad replacement, crooked ABS sensor, dirty abs sensor, broken wire to the abs sensor, crud on the any of the connections going to the ABS/master cylinder/reservoir, air in the brake system (replaced a caliper lately?), the pin that sits above your brake pedal that unlocks your shifter can go bad... all of these can cause the abs/brake!/VSC TRAC/VSC OFF lights on your dashboard to light up, along with the beeeeeeeep. Just plugging in an OBDII scan tool can cause the lights to go off. Even if you get them to go off they get stored in the computer and will keep coming back randomly like a disgruntled ex.
Ok..now to put that paperclip to use. Unwind it and make it into a big V.
With your key turned fully OFF, Find your OBDII port under your dash and plug the paperclip into pin holes 13 and 4. Here is a diagram
http://www.obd2.com/graphics/ease/obd2dlc.gif
Make sure you're looking at this diagram correctly and not upside down. Double and triple check before you push in the paperclip.
Once you have the paperclip in pin holes 13 and 4 get in... sit in your drivers seat. This next task needs to be done quickly.
Turn the key all the way on but don't start it.
As soon as you have the key turned to on... Pump the brake pedal 8 times in under 5 seconds and wait for the abs/brake!/VSC TRAC/VSC OFF lights to turn off.
The exact moment the lights turn off you have to turn the key back off. If not, the ABS/VSC/etc will start flashing very quickly. If they start flashing you have to start over.
This took me 2 tries to get it right.
With the key off you can now pull the paperclip out.
You've just cleared the codes and hopefully solved your problem.
After months of dealing with this, I haven't had the lights/beep come on in a while since performing this simple and free task.
Good Luck man.. let me know if it works.
Things to note.
Before I performed this, I removed the rear right brake caliper and greased the caliper slide bolts. One was rusty and I suspected it was the cause of the lights in the first place because it could have been read as a seized caliper by the abs sensor. (two years ago my front drivers side caliper was seized and caused the lights/beep to come on)
I also performed a zero point calibration, but it did not help.
https://www.youtube.com/watch?v=55XmiSsGQgo
I unplugged every connection going to the master cylinder/abs pump/abs unit and removed and inspected the pin that is connected to the brake pedal. All were clean.
And i checked every wire going to the abs sensors to make sure they weren't cracked or damaged.
The reason why these lights come on from something completely unrelated like a bad Oxygen sensor or loose gas cap is because the computer is protecting the engine. VSC/Traction control use the engine to do their job.