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Discussion Starter · #1 ·
Hi!

I have two related problems:
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Automotive lighting Speedometer Odometer Gauge Trip computer


While ABS actually works, stabilization does not (it is always off).
I read the error from the ABS unit - it's a yaw sensor error.
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But at the same time the data from the yaw sensor are successfully read (zero values are when the car was stationary).
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Does this mean that the yaw sensor is actually working properly and the problem is something else?

Thanks for your help!
 

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Car stationary- yaw sensor should be returning a null value. If it is not, the yaw sensor is defective. It happens occasionally but before you change it, just make sure it is secured to the floor of the car and the wiring is not damaged.
 

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It's not a problem I've had, but I'm fairly sure I've read similar here before. Try a search in this forum. I think that turned out to be that the tracking had been set without the steering wheel in the straight ahead position. This created a VDC conflict between yaw sensor null and abs wheel sensors showing unequal equal wheel rotation. Getting toe-in
correctly adjusted was all that was needed. I think!
 

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It's not a problem I've had, but I'm fairly sure I've read similar here before. Try a search in this forum. I think that turned out to be that the tracking had been set without the steering wheel in the straight ahead position. This created a VDC conflict between yaw sensor null and abs wheel sensors showing unequal equal wheel rotation. Getting toe-in
correctly adjusted was all that was needed. I think!
I had the same problem with my GT but the same alarms didn't register until the car moved or the wheel was turned. It required the steering wheel to be re-aligned (set to 0 degrees when straight) with a scanner. Two minute job providing you have the correct tool to reset it. Good luck :)
 

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Yes, the steering angle should be zero when the front wheels are straight but it doesn't account for the yaw data. I suggest checking the voltages ideally with an oscilloscope to see if the raw data concurs with the output data from the ABS module.
 

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You could first try to re-calibrate the steering angle sensor to see if resolves the situation (it's located under the steering wheel).

Simply find a large flat area (empty shopping centre car park), drive the car in a straight line for a short distance, at a slow speed, without touching the steering wheel. This will set your steering to pretty much straight ahead, then carry out the steering angle sensor calibration.

If this does not fix your problem then check the connections to the yaw sensor, if still no luck, replace yaw sensor.
 

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Discussion Starter · #7 ·
Hi!

Tried to calibrate the steering angle sensor, but failed:
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It must be because of my scanner. I have a very inexpensive one:
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However, when I stopped the car using the method suggested above, the steering angle sensor showed 0.

And then when I drove, the steering angle and yaw graphs were very similar to each other:
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I guess that's how it's supposed to be.

That wasn't the case last time, so I should probably take a closer look at the yaw sensor.

Thanks for your comments!
 

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The old thread, as I remember, wasn't about yaw angle calibration to steering wheel position. It was about the consequence of adjusting tracking unequally, with the steering wheel not set centrally/straight ahead. The result is unequal wheel rotation (as detected by ABS) when steering angle is null. The wheels are not set in the straight ahead position when the steering wheel is. That's a mechanical mismatch that VDC sees as a fault. No amount of calibration will fix this physical wheel misalignment. One track rod is set longer than the other. It needs the tracking done properly, with the steering wheel in the straight ahead position.
 
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