Hello! Hope I'm posting in the right thread...
I have a 2003 MONTE CARLO SS... Just got in the car and a SERVICE TRACTION SYSTEM warning came on as well as the ABS LIGHT. I also noticed that the TRAC OFF light is lit... What is the common cause for this? Is it safe to still operate my vehicle? Checked the fluid level and it looks ok. I should point out that I have an ongoing BCM problem with this car. My service engine light has been on for awhile. Right now, can't afford to take it to GM to have it replaced and or reset. The BCM has been effecting a lot of systems throughout the car including shifting, locks randomly activating and more. Is the TRACTION SYSTEM part of the BCM? I ask because before I go and have my local mechanic fix something that may not "really" be broken. That happend with my fan control switch among others... Any help/info would GREATLY be appreciated!!!

THANK YOU! Chad

 

Every wheel has something called a Wheel Hub Assembly on it, behind the rotor.

This holds speed sensors and those sensors can get wet and throw false readings. You can check the wires and the grounds to make sure everything is clean and if you still have this issue, you will have to have someone with an ABS code reader look at the code and determine which wheel sensor is giving the bad code. Then you will have to replace the wheel hub assembly.

http://www.paulstravelpictures.com/G...ent/index.html

There is a good write-up on how to replace the assemblies.

There is also a ground under your air box where the PCM is that could be dirty and throw this problem.

As for the fluid, if the fluid gets low you will have a BRAKE light illuminated on the dash.

Also, it is safe to operate your car while this is happening just be warned that you will not have ABS or your Traction Control System. So be careful in the rain and poor weather, especially if your tires aren't in the best condition

 

THANK YOU! That was super helpful! Quick question, you mentioned a BRAKE light on my dash... Is this different from the ABS light I'm getting now? Are the SPEED SENSORS actually part of the WHEEL HUB ASSEMBLY itself? From the link you provided, it looks like a seperate part. In other words... Is it possible to replace just the SENSOR? or, if indicated by the ABS READER that means the whole W.H.A. is bad? Basically wondering if they are two seperate parts or if ordering a new W.H.A. comes with a new sensor? and finally, are the sensors controlled by the BCM? THANX AGAIN!

 

BRAKE light would be only if your fluid was low, I was just mentioning it since you said you checked your fluid.

The sensors are built in unfortunately to try and keep water out, just the connector with the wire is what you see. Which is what you could check for water or dirt.

I'm not 100% if it's the PCM or the BCM that controls the signal

 

I had the same abs/traction control lights lit. Autozone had free ABS code scanning that said there was no signal from the right front wheel and said the hub assembly would need to be replaced. Before doing that I decided to check the abs wiring harness and connections. Connections were clean but when I tested the harness I found there was a break somewhere in the wiring (nothing externally visible). If you have a digital multimeter you can test this yourself using the Ohms setting.

Remove wheel in question, assuming the error code indicates which one.
Disconnect the connector by the brakes.
Unwrap the plastic casing or tape about two feet or so from the wheel connection to expose the two harness wires.
Remove a very small section of the wires insulation, just enough to allow the meter probe to contact the wire. I used a nail clippers for this. Be careful not to nick the wire itself.
Test each wire by placing the probe against the wheel connection contact and the exposed wire further up the harness.
If the meter reads more than practically zero the wire is bad.

I replaced my faulty section of harness for 35 dollars and 20 minutes of work and everything works great now.

Hope this helps, worth ruling out the harness before replacing hubs.

 

im having the same problem, but I changed my wheel hub and the lights are still on. the abs and trc control warning. tell me more about this ground wire. how do i get to it? know of a link with a how-to?

 

Norwex,
It's actually the abs wire harness. The abs wheel sensor is in the hub assembly itself and has a short wire coming out of the hub and connecting to the harness right by the brake caliper. The harness then runs toward the front of the engine where multiple other wires meet. If the harness does prove faulty it can be easily replaced by cutting out the old one and splicing in the new wires (only 2). You just have to make sure to wrap the spice good to keep moisture out. I actually put some silicone sealant over the spliced/taped section to be double sure. Here is a picture of the harness for my 2001

[IMG]file:///C:/DOCUME%7E1/Owner/LOCALS%7E1/Temp/moz-screenshot.png[/IMG]harness.jpg

 

I had to do this on wife's 2001 impala ss, front hubs had some play so I replaced Light was still on till I replaced wire now lights off 4 months now .....

 

yea i will have to look into it as soon as it warms up. i replaced the hub assembly, but i know it needed to be replaced because it was so loud when i was driving. I figured as soon as i replace the hub the light would go off, but it didnt. is it supposed to turn off by itself of does it have to be taken in to get reset?

 

on my 2001 the light went off and has 100% stayed off after the harness was replaced, no reset needed.
Have you had the system scanned to see what the error is? You need to use a separate ABS scanner or an code scanner that also had ABS capability. Try Autozone, O'reilly, Advanced Auto etc. and see if they offer free ABS code checks. That worked for me.
My code said that it wasn't getting a signal from the front right wheel and they suggested replacing the hub but if the harness is bad of course it won't get a signal!
I know there was a technical service bulletin about the faulty harness affecting montes, impalas, gran prix's and probably more GM cars.