I have a 2001 alero (4 cylinder) with 145K miles on it. ABS, Low Trac,
Service Light and sometimes Brake Light are on as soon as my car is in
motion(Lights are not lit initially when I turn the engine on. As soon
as I change the gear from parking to reverse or drive they all are
lit). I took it to Autozone for error code lookup but no codes were
reported. I gave it to the dealer for checkup. The dealer initially
said it will cost $80 for diagnostic but he called later in the
afternoon and said it might require 3 to 4 labor hours to diagnose the
problem and will cost me $200. I backed off. I don'[img]smileys/smiley25.gif[/img]t know how much more
life the car has so don't want to spend too much on it. I live in Texas
which requires annual vehicle inspection. I am already due for the
inspection. My vehicle will not qualify for inspection as the lights
are on. Is there any way to diable the lights and get the state
inspection done or any other alternative? I don't want to spend like
1000 bucks on this car and then trash it in a year.

I had a similar problem with my 2000 Impala, which turned out to be low brake fluid. Check that your reservoir is all the way up to the full mark. Sometimes hitting a big pothole (or very deep snow) can knock a wheel sensor loose, which will cause brake, ABS, and (maybe) low trac to come on. I've got an 01 Alero, and I'll check where the wheel sensors are tomorrow, so I can tell you where exactly to look.


Did all the lights come on at once, or did they come on one at a time over a few days or weeks? Have you had any work done to the car recently? Has the braking performance, feel, or sound changed? Some warning lights can be reset by disconnecting the battery for five minutes. This may not solve your problem, but it's worth a try.


Ask the dealer which codes were shown when they scanned the car, and post those codes for me. $80 to read codes at a dealer sounds about right. Autozone probably doesn't have a TechII scanner, which is the only one that will show all the codes a GM car can have. Autozone will normally only be able to read engine codes.


The only way I know of to disable the lights is to unplug the instrument cluster, which would be pretty obvious to the inspector, and would not fix anything anyway.

Hi,
We have a 2001 and ours has only 54,000 miles and the same thing started happening (same lights) the day we got the oil changed at a
national chain. Do you know where you check wheel sensors?

Did you have any luck fixing the problem? Had the emissions checked and they are fine.

i have 2001 alero and have the same problem.But for me, sometime it goes of and sometimes it comes on. I recentlywent to get my car serviced and they went through the computer to see what was wrong with it however, nothing was detected......


let me know what is wrong with it.





thanksEdited by: gregyoon

Check the wiring harness to the wheel sensors. The front harnesses are more likely to be bad than the rears. There is only one set of 2 or 3 wires going to the wheels. Trace it to the connector in the hub, unplug, and look for corrosion on the contacts. These harnesses are known to break on these cars, especially the fronts.


A harness with an intermittent short may not store a code, because the computer will only show a code when the harness has the short. By the time the car is scanned, it may not be showing anymore.

I just bought a 2003 4 cyl manual with 36,000 km's. In two months I've already put another 20,000 highway kms on it and I plan to put a lot more.


I have the ABS, Track Off, Check Vehicle Soon lights also. They are off every time I start the car. Sometimes they don't come on for 20 minutes ofdriving but sometimes they come on as soon as I start to move. Once in a while, I'm driving within the first 20 minutes and they are off, when I use the breaks, the ABS system activates with the noise and pulsation in the break peddle for an instance then the lights come on and the ABS seems to be deacitvated. All this in dry warm weather on ashphalt.


My little $100 obdII reader does not read any codes after the lights come on.


I'm starting to learn that thespeedsensors that the ABS and Traction Control systems use are in the front wheel bearing and I have to replace the entire bearing to replace the sensor. They seem easy to replace and cost $90 for the cheap one and $170 for the better quality one.


The repair seems easy enough if you can change pads and have access to torque wrench and bearing puller.


So I'm getting ready to give it a try with the better timkken bearing. Any comments from this forum on the difficulty of the job or this brand of bearing?

good luck fixing it and let me know if it works.....


i need to fix it as well

I need to fix it as well. Please let us know how it goes.

Good luck

Like I tell my team, Luck has nothing to do with it. Here's what I plan to do.


1. check/clean all the connections at each wheel and look for broken wires. If that doen't fix it then on to step 2.


2. buy a hub and put in on one side. If that doesn't fix it they I'll move it to the other side. Since my bearings are actually ok there is no danger driving it with the old parts.


I've seen a $75 part and a $175 Timken part, and a made in the usa part from the dealer for $422.


I'm putting the timken one in.


I was hoping someone could tell me how to electrically test the speed sensor before I take it off the car.

A Tech II scanner can determine which hub is bad, if the problem is the wheel speed sensor, which is built into the hub and cannot be removed separately. There is no way to electronically test the sensor before removing the hub, and without the tech II, no way to determine which sensor is bad. You have a one in four chance of getting it right the first time, since the computer uses signals from all four hubs for the ABS and traction control.