My 1999 ES300 has the ABS light coming on (steady on) accompanied by the traction control TRAC light blinking (which makes sense - problem w/ ABS, problem with TRAC).

But it's intermittent. I can start the car, the lights are off and if I test ABS (on sand road) it works - I can feel / hear the brake chatter.

But after driving for awhile, the lights will come on. I'm guessing that the sensors at each wheel are okay then. But there is a loose wire connection somewhere.

Help - how can I troubleshoot this? And is there anything else this could be (and if so, how do I check)?

Or should I just take the car to a shop? This is one of the reasons I'm looking into jacks. I thought I might be able to save some money by fixing this (if simple).

This message has been edited. Last edited by: konata88,

The normal reason for this is that a sensor is having a problem. Traction control and even cruise control going off line with it is nothing. Of course the difference between the sensor and wiring is not something you can easily determine. But first step is to see if your system (they vary) will tell you what sensor it is. Then you can look further. Many issues in older cars are the backing plate is gone, someone has installed aftermarket bearings, there is corrosion on the sensor ring. But at this point in the car's age, its probably just the sensor. The ABS module itself can go, but that's rare at least, but very expensive. So if you have access to a decent scan tool, the simple project is to pull the code and see which one, swap the sensor and see where you are. after that its more difficult.

It could be a abs wheel sensor, could be dirty, broken wire, or sensor failure. Most of the major parts stores will scan your truck for free. That will help narrow down your issue.

Thanks guys.

So, I can go to any major auto parts store and they will scan the codes for me with no obligation? I'd feel a little bad since I tend to stick w/ factory parts (and as such, you would think a dealer would provide a scan service). But I'm guessing dealers won't scan for codes for you - no incentive?

Okay - I'll try to have an auto parts store scan for codes and then maybe look at the suspect wheel. Check the sensor mechanically and for resistance (1.5 ohms?) and maybe wiring. Replace if I find an issue. After that, I guess it's too difficult and complicated and so off to the shop?

My truck has a leak in the system and SLOWLY leaks brake fluid. The ABS light comes on when the fluid gets low.

Check the level of the brake fluid before you do anything.

Thanks. Checked. Fluid level looks good.

I had a similar problem with my wife's 2005 Ford Escape with the Service an Trac lights. Turned out to be the "tone ring" on her right front had cracked and under certain conditions would not spin at the correct speed. They are pressed fit.

Had trouble with the traction control light on a 2012 Sierra I had...turned out to be the steering position sensor.

Should I invest in one of these? Will this work for 1999 Lexus ES300 through current model year Toyota / Lexus? Or will I have to pay for multiple sw versions?

I saw a Solus model but that costs several thousand dollars (I had to look twice - I thought I was mistaken).

https://www.snapon.com/diagnostics/us/MICROSCANIII

Having a parts store scan your car and getting the part from them, given the age of the car, Might be a good idea if there is a difference in their price and OEM. It looks like some of the Lexus ABS sensors may be $300+ from the dealer. You could also get the wheel located by their scanner then go home to pull that wheel and check the wires.

quote:

Originally posted by Greymann:
It could be a abs wheel sensor, could be dirty, broken wire, or sensor failure. Most of the major parts stores will scan your truck for free. That will help narrow down your issue.

^^^
This,have the same on an 06 jeep,happen every I take a left turn.
I have the replacement cable and I have to get my old ass to work.
Quite a job,caliper has to come off as well as the bracket.
I should know cause I went to pull a part for practice to get one.

Went to a store and no codes were showing because the ABS light wasn't on. No history stored.

I'm guessing it's a loose connector somewhere since it's intermittent. I drove all the way to the store and the light didn't come on. Of course, it came on as I'm pulling into the driveway.

It may be hard to capture the code - especially if the car needs to be off to connect the scanner. The ABS light seems to reset each time the car is turned off. It comes on after driving for a period of time.

Is there a good but cheap code scanner that would come in handy for my Toyota's? Could I keep it connected while driving?

Did you have tire or brake work recently? If there is no code, there's no code. Assuming you or the manager used the scanner correctly.

I *think* that happened to me ages ago. It meant something else, like a bad transmission shift solenoid or something else (removed, cleaned with brake fluid, reinstalled, no more light). My ex-wife's Subaru will have a blinking cruise control light come on (and no cruise control) when there is a specific issue - I think it was a loose fuel cap.

A '99? It could be the brake fluid level sensor. If you unplug (or bridge/close the circuit) the sensor, what happens?

Time for clublexus.com? I love auto forums. Volvo, Acura, Subaru, now Chevy/Sierra.

_{My 'banging clattering wipers acura tl' writeup made me an internet star}

No work recently. The ABS light is coming and going. Not sure what triggers it to come on. But turning the car off resets it.

Bumps, hard braking don't trigger it. I was driving slow and smooth in the neighborhood when it came on.

If I can get sense if the problem is wheel specific or central, it may help narrow down the candidate list.

Looking at this OBD2 reader: https://www.amazon.com/gp/prod...A35MJKSRDMB5RO&psc=1

You might check out a Scangauge OBD2 reader. I got one on amazon and installed it in my 2001 Suburban. It was an easy 5 minute job. I leave it hooked up all the time to monitor mileage, coolant temp, couple other things.

This intermittent type stuff is typical of the wheel sensor and ring, not something else. There is a tolerance built into the system and then after some time it throws a code as it sees too much difference in reading. In terms of reading it once it comes on, don't shut off and get it read. In many cars (don't know about yours) you can get the system to tell you which wheel with some combinations of operating various switches etc. that don't need a scanner. But me, if I'm going to own a 1999 I'd get a good scanner.

Scangauge looks cool but it doesn’t seem to help with ABS.

quote:

Originally posted by hrcjon:
But me, if I'm going to own a 1999 I'd get a good scanner.

Is there an ABS capable scanner under $200 that you would buy?

Some scanner will only read engine codes only and they are not able to read abs and transmission codes. And most scanner can be left plugged in while driving. But it sure sounds like a dirty sensor, they are magnetic and metal dust and crud will give intermittent problems as well as broken ring.

quote:

Originally posted by hrcjon:
This intermittent type stuff is typical of the wheel sensor and ring, not something else. There is a tolerance built into the system and then after some time it throws a code as it sees too much difference in reading. In terms of reading it once it comes on, don't shut off and get it read.

This usually is the case, and a good way to have the codes checked. The computer will reset and will do a self test each time the ignition is turned on. If the sensors are in parameters, then no lights and no codes.

Looks like the computer is losing the signal from one or more of the speed sensors. This could be from a faulty sensor, dirt or grime, clearance issue, or wiring.

A graphing scanner would be a great asset to help determine which sensor or circuit is suspect. Set the scanner to graph each wheel sensor at the same time, then drive the vehicle. Pay the most attention when first moving and when slowing down close to stopping. You want to see all of the sensors graphing the same speed at the same time. What you may find is one sensor may be slow to react, or may drop out. This would now be the place to start looking. Many times a good cleaning may remedy the issue, or the reluctor could be bent or damaged, or the sensor can just be bad.

The Snap-on MicroScanIII that you reference will graph some data parameters. I'm not sure if it will graph ABS data though.