ABS system and Traction System
As i drive and apply brakes, sporadically, the brake pedal will give a little and be harder
to start. Then I hear a beep and the light symbols for the traction system and abs
system comes on on the tachometer area. In the DIC it will read service abs system
and service traction system. Then it will tell me the traction system is off. My
boyfriend checked brake pads, does not need any. But said it was very UNUSUALLY
hot. What else needs to be checked?
Separate the wheel sensor harness connector at each wheel and carefully clean the contacts, Apply a little dialectric grease and reconnect everything. Those connectors get corroded over time and will send false or erratic signals to the ABS and Traction program. This can cause the symptoms you're getting.
For some reason worn out front wheel bearings can sometimes mess with the ABS. It's happened on cars of mine twice. Most often I noticed the symptoms during low speed turns.
Did anything work to fix your problem?
Yes, changing out the front wheel bearings cured it. It's a good time to consider changing out the axle shafts too if its in the budget and they are high mileage. I like Norm's advice up above too though, and its cheaper than bearings and axles. I'd go there first.
so I have a 2007 Pontiac Grand Prix everytime I hit my break pedal almost every time I hit my brake pedal it's like I'm sliding in snow my abs comes on mi pedal shakes like I'm sliding and my traction control light comes on and ABS light comes on does anyone know why that is?
Yes, it is likely one or all of three things. Possibly a failed wheel sensor. Possibly a failing CV (front axle) shaft and maybe a bad front wheel bearing. My feeling is its more likely an axle shaft than a sensor. I think sensors get blamed a lot of times when they are simply reading other mechanical problems. I've owned lots of GM front wheel drives, and I've had that sort of problem on several of them and it has always been cured when I changed out axles and bearings. Do you feel a vibration in the steering wheel when you are simply driving down the road at various speeds? That's a sure sign of a faulty axle, and a dull roar/rumble, sometimes barely audible is often a sign of a failing bearing.
We changed the wheel bearing and it was good for a week and now same problem. All lights and messages on for abs and traction.Put it on the machine and it said it was right front so that is the one we changed.
Could be the other bearing as well. They both have the same number of miles on them after all. And of course there are sensors down there which can fail. Remember we're all just guessing here because none of us can see or drive your car. You could just drive it for a while and see what happens. Or you could find a good front end shop to do some diagnosis. If its in the budget, you probably can't go too far wrong by changing the other bearing and seeing what happens.
Would you possibly think it's the Pedal Senor ? For the acceleration
First of all your CV axles have nothing to do with traction control they merely propel your tires, your sensors if you notice are getting a reading from a ring of teeth which the CPU takes and applies to an algorithm and deciphers it to know how fast each wheel is rotating and when on ice where the abs comes in is when a tire is turning and the rest aren't your brakes release and apply a hundred times a second in relation to the rings teeth the sensor is detecting that's turning. There is a small gap between the sensor and teeth so yes the hub bearings can alter the readings and make the CPU send a fault
RE:We changed the wheel bearing and it was good for a week and now same problem. All lights and messages on for abs and traction.Put it on the machine and it said it was right front so that is the one we changed. When you changed the bearing you might have allowed some contact in the sensors connection you might do as Norm suggested I believe separate the sensors connector and using electrical contact cleaner clean the two connectors and apply di-electric grease and that should remedy your dilemma? If not then your sensor may need to be replaced?
Some of the threads I have read elsewhere have been talking about a weak area of the wiring harness leading to both front wheels. It appears that many people have had corroded wires or broken wires connecting the wheel sensors to the control unit. This was found by checking the voltage output at the control unit and then periodically on the wires leading to the wheel sensors. There has been a noticeable voltage drop or absence of voltage just past the problem area of the wire. A repair splice of the wire or replacing all the rest of the wire leading to the wheel sensor has done the trick. As I understand it, GM sells a new wheel sensor connector and short segment of wire. Why would they do that if this were not a problem they are aware of?
Apparently it is a problem they are aware of. That's why they sell a sensor connector and short segment of wire. It's a service part. Cars don't last forever. As they get older things need repairing.
Sorry no offense but, people who know nothing about cars except how to drive them exist however Munron is right they've had hundreds upon hundreds of the same problem with that same model so rather than do a recall update and waste money they have number crunchers figure out what it will cost to make these repair kits and wait for customers to come in as these problem areas arise! That would explain the symptoms reported so I would try that first, A. Because it is certainly the least expensive repair and B it just seems logical and Drqueztv, please sarcasm isn't necessary!
My apologies Drqueztv I misread your comment I figured you were being sarcastic and no it has nothing to do with acceleration that's engine management we are on the area of braking and traction control!
munron or james, do either of you know what the actual name is for the sensor connector and segment of wire kit? is it Dorman 970-047 ABS Wheel Speed Sensor with Harness
Yes, after reading the description I would say that's the part you're after. It appears to be just the wiring without the sensor despite the badly worded description.
Munron how do you know so much of car
For my own problem front left and sensor was causing TC and abs light to come on... In order to fix my issue, I spliced the wires from the speed sensor arness. There is a week spot in the bend .disconnect it remove it from the holders and start opening up the wire shell. There will be a rubber shell as well. Carefully cut open with exacto knife fix week spot and clean the connector pins while you're at it !!! Only issue I still have is if I go wide open throttle it might turn abs / Tc lights on if I shut the car off and restarts the errors are gone
i have this problem with my 2007 grand prix, I had the bearing replaced and about a month later it started again
If you used a cheap Chinese replacement and the problem went away and is now back I would suspect the bearing/sensor is at fault again. If you used a good quality brand name part, then I'd look at other parts of the wiring harness or perhaps a different wheel is at fault.
If I have replaced the wire harness and no more lights come on but now when I apply the brakes and sit at a stop light my car starts vibrating and it sounds like some sort of pump then when I shut off car it sounds like the pump is either filling back w air or fluid for a second after the power is shut off?
Scan it for trouble codes and see what comes up.
They have scanned it 3 times now after replacing wire harness and no codes or lights ever come on so I am at a loss why none of these places have an answer when I take my car in
Changed a section of the wiring harness in the front on both sides.PROBLEM SOLVED after 2 years!!
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