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warning lights, 2001 olds alero

The TRAC OFF, ANTI LOCK and the ever popular SERVICE ENGINE SOON intermittently
<br/> come on. No other vehicle symptoms are noticeable when they come on. The lites always turn off and stay off by restarting the engine. I've seen/heard various fixes;
<br/> wheel speed sensors, throttle position sensor, O2 sensor, wheel bearings ets.
<br/> Right now the problem is nothing more than a nuisance. Just wondering if anyone has come up with a solid fix to this problem


  • edited June 2010
    Well, the problem is that there isn't a "this" problem. Between the ABS/TRAC and SES lights you're looking at any one of hundreds of possible problems. These two lights might also be related to the same problem - or maybe even two completely different ones. There is no one solution, nor will you get anywhere guessing.

    For the ABS/TRAC issue at the very least pop the hood and check the level of the brake fluid. If it is low add some and then have your brakes evaluated asap.

    But in general, these lights are associated with stored error codes, and the way to get started on finding the problem(s) is to have it scanned for codes. Large chain auto parts stores (e.g. Autozone) will scan for free - but their scanners will only get what is associated with the SES light, not the ABS/TRAC. For that you'll want a local shop that does brakes.
  • edited June 2010
    There's no reason to guess about this. You need to get the DTCs read. Unfortunately, you will have to go to a dealer or an independent with a GM specific scan tool to get the ABS codes. I suspect that all three are related. A fault with the ABS causes the traction control to shut down because it uses the ABS for control. If the ABS fault results in it not being able to tell the PCM how fast the car is going, you will also get a Check Engine Light. It may just be a wheel speed sensor, but getting the ABS codes will tell you where to start looking for the problem.
  • edited June 2010
    Double check what exactly that third warning light says. Your Alero also has a 'service VEHICLE soon' light, and that is what generally comes on along with the ABS and trac off lights. The most common causes of these lights coming on in these cars are bad wheel speed sensors, which are unfortunately integrated into the hub assemblies, or broken/chafed wiring for the wheel speed sensors. Get the codes read to narrow down where the problem is located so you can start looking for the problem.
  • edited June 2010
    There may be a common power source to those areas that is having trouble so check that out.
  • edited September 2010
    Mine does the same thing usually only upon starting up. I usually stop. Turn off the car and restart and things go on without the lights.

    Let me know if you find out more.

  • edited September 2010
    I have a 2000 olds Alero with 109K. The 3 warning lights were on since I picked up the car in June. Before a tune-up, I was getting 23.5 MPG. That's pretty poor for a I4. After a tune-up(oil/filter/plugs/airfilter) R front wheel bearing change, 28.2 MPG. I had a friend use a GM code reader and it told me I had a bad R front wheel bearing. I checked NAPA and it was $89 or $139(1 year warranty). I went on eBay and picked on up brand new for $34.95 shipped with the same warranty! An hour later, I had the wheel bearing installed and I now have ABS for the first time and all 3 idiot lights are OFF!!
  • edited September 2010
    I have worked on cars before that trips the TRAC OFF light when the check engine light comes on. So it could just be one problem with the CEL code or codes. Have codes pulled and post the Code Numbers, not the description that some mechanics or part stores give for the code. Have them clear the codes after you retrieve them and it will probably reset the TRAC OFF light to.
    There are places that pull these codes for free. Most auto parts store will retrieve them for you for free.
  • edited September 2010

    "I had a friend use a GM code reader and it told me I had a bad R front wheel bearing."

    Please get us the exact make and model of that code reader.
    I want one of those!
  • edited September 2010
    I'll check on the Code reader. My SES light is on in my 2003 Trailblazer and now in my 2004 Envoy XL. I had 3 codes read to me on the Alero & cleared, but as soon as I got down the block they went on again. I'll see if I wrote down the specific codes.
  • edited September 2010
    Implausible on the face of it for sure. But I'm pretty sure that those are bearing/speed sensor assemblies - with the wheel speed sensor built into the bearing. So I'd guess that what the scanner reported was a RF speed sensor malfunction - which means that you have to replace the whole bearing assy.
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