TCS Engaging for no reason
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TCS Engaging for no reason
I've had some strange problems with the TCS recently, a few months ago I noticed it was turning itsself off randomly while I was driving. This was under normal conditions like freeway cruising speed. It wouldn't turn back on if I pressed the button no matter how many times. but If I restarted the car it would turn on again.
Now this week I noticed that it started engaging the "low trac" and activiating the TCS to the point where I couldn't accellerate the engine, and at first I thought it stalled out because I literally had it near floored and got no engine revs. When I turn TCS off the car goes back to normal.
I think the rear end may be going but there are so many parts back there I have no clue what it would be, I don't want to start throwing parts at it. A new rear end would probably be just as cheap. What are the other possibilities, maybe an electrical connector or something is loose? No idea, couldn't find much about this problem searching though.
Now this week I noticed that it started engaging the "low trac" and activiating the TCS to the point where I couldn't accellerate the engine, and at first I thought it stalled out because I literally had it near floored and got no engine revs. When I turn TCS off the car goes back to normal.
I think the rear end may be going but there are so many parts back there I have no clue what it would be, I don't want to start throwing parts at it. A new rear end would probably be just as cheap. What are the other possibilities, maybe an electrical connector or something is loose? No idea, couldn't find much about this problem searching though.
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If the car drives normally with the TCS off, I would think you have an electrical/sensor problem. Since your low track light is coming on, the system senses a tire slip. This is something you definitely want to fix as the same electronics feed your ABS system.
Do you have any other lights on in the dash cluster? Have you changed wheels, tires, or gears recently? If not, I'd start by checking the rear (the fronts are built in to the sealed hubs) ABS sensors to make sure they are in the correct positions and reading the wheel correctly. If all looks good there, scanning the ABS system (a high end scanner is required for this) may give you a clue as to which corner of the car the problem is on.
Do you have any other lights on in the dash cluster? Have you changed wheels, tires, or gears recently? If not, I'd start by checking the rear (the fronts are built in to the sealed hubs) ABS sensors to make sure they are in the correct positions and reading the wheel correctly. If all looks good there, scanning the ABS system (a high end scanner is required for this) may give you a clue as to which corner of the car the problem is on.
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If the car drives normally with the TCS off, I would think you have an electrical/sensor problem. Since your low track light is coming on, the system senses a tire slip. This is something you definitely want to fix as the same electronics feed your ABS system.
Do you have any other lights on in the dash cluster? Have you changed wheels, tires, or gears recently? If not, I'd start by checking the rear (the fronts are built in to the sealed hubs) ABS sensors to make sure they are in the correct positions and reading the wheel correctly. If all looks good there, scanning the ABS system (a high end scanner is required for this) may give you a clue as to which corner of the car the problem is on.
Do you have any other lights on in the dash cluster? Have you changed wheels, tires, or gears recently? If not, I'd start by checking the rear (the fronts are built in to the sealed hubs) ABS sensors to make sure they are in the correct positions and reading the wheel correctly. If all looks good there, scanning the ABS system (a high end scanner is required for this) may give you a clue as to which corner of the car the problem is on.
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Does a code get stored each and every time thsystem is activated? I am curious because if that was the case, if there is a poor signal between the sensor and reluctor ring, the system would read it just like any other loss of traction such as driving in snow. Would the code only pop for a legit malfunction of a part or does it happen upon every activation. I have 3 channel so I have never looked into it.
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Interesting. I didnt know that. Like I said, I have 3 channel so I do not have traction control. Funny thing is, after I swaped from A4 to M6, my low trac light will come on sometimes and I don't even have traction control. Strange. It doesn't effect my engine performance or anything so I just let it be.
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This is the "ABS INOP" light.
The "LOW TRAC" light will come on when your ABS system senses a wheel slip or when the traction control system is working. (They use the same sensors.)
If you don't have traction control, aren't slipping, and the light comes on, the system is incorrectly measuring differences between what the sensors report the wheel rotations being vs. what the system expects.
Interesting. I didnt know that. Like I said, I have 3 channel so I do not have traction control. Funny thing is, after I swaped from A4 to M6, my low trac light will come on sometimes and I don't even have traction control. Strange. It doesn't effect my engine performance or anything so I just let it be.
If you don't have traction control, aren't slipping, and the light comes on, the system is incorrectly measuring differences between what the sensors report the wheel rotations being vs. what the system expects.
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This is the "ABS INOP" light.
The "LOW TRAC" light will come on when your ABS system senses a wheel slip or when the traction control system is working. (They use the same sensors.)
If you don't have traction control, aren't slipping, and the light comes on, the system is incorrectly measuring differences between what the sensors report the wheel rotations being vs. what the system expects.
The "LOW TRAC" light will come on when your ABS system senses a wheel slip or when the traction control system is working. (They use the same sensors.)
If you don't have traction control, aren't slipping, and the light comes on, the system is incorrectly measuring differences between what the sensors report the wheel rotations being vs. what the system expects.
#10
Is it the TCS activating or is it the ABS pulsing?
ABS will pulse if it senses a wheel speed differential, and wont set a DTC unless it sees the circuit is malfunctioning. If the circuit is mostly intact, it will activate because it thinks its doing its job.
Usually the way to tell is to drive with a scan tool and inspect the ABS wheel speed data. the faulty wheel will tell you which sensor is bad.
9/10 times, its usually the harness pigtail going to the wheel speed sensor itself. if you can pull on the wiring harness and it snaps, thats where the problem is.
if you pull on it and it is firm, its more of a sensor issue.
hope that helps somewhat.
lets put it this way: ive replaced hundreds of wiring pigtails for the issue, and every now and then it ends up being the wheel speed sensor/wheel bearing.
ABS will pulse if it senses a wheel speed differential, and wont set a DTC unless it sees the circuit is malfunctioning. If the circuit is mostly intact, it will activate because it thinks its doing its job.
Usually the way to tell is to drive with a scan tool and inspect the ABS wheel speed data. the faulty wheel will tell you which sensor is bad.
9/10 times, its usually the harness pigtail going to the wheel speed sensor itself. if you can pull on the wiring harness and it snaps, thats where the problem is.
if you pull on it and it is firm, its more of a sensor issue.
hope that helps somewhat.
lets put it this way: ive replaced hundreds of wiring pigtails for the issue, and every now and then it ends up being the wheel speed sensor/wheel bearing.