Active Handling Warmup
10-28-2014, 11:44 PM
#1
Active Handling Warmup
I'm using a C5 6sp in autocross. During a run I get a active handling warming up signal. The warning turns off after the run is complete. If I let the car idle between runs I get no warning. I don't remember this happening last spring. How can I avoid this problem?
10-29-2014, 01:13 AM
#4
Normal unless persistent/warning. It's establishing a baseline to calibrate wheel speed sensors. Lots of info already if you do a search... some examples:
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...g-problem.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...arming-up.html
- https://www.corvetteforum.com/forums...g-problem.html
- https://www.corvetteforum.com/forums...arming-up.html
10-29-2014, 02:47 AM
#5
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The AH resets with each engine start. The first thing it does is calibrate itself so it knows when the steering wheel is pointed straight ahead. To finish calibration after engine start the car has to be driven in a straight line for a certain distance at a speed above 6 mph. If you want to use AH while autocrossing then park you car a couple hundred ft from the starting line so when you start the engine you can drive in a straight line above 6 mph.
Bill
Bill
10-30-2014, 12:45 PM
#8
Race Director
The AH resets with each engine start. The first thing it does is calibrate itself so it knows when the steering wheel is pointed straight ahead. To finish calibration after engine start the car has to be driven in a straight line for a certain distance at a speed above 6 mph. If you want to use AH while autocrossing then park you car a couple hundred ft from the starting line so when you start the engine you can drive in a straight line above 6 mph.
Bill
Bill
But don't worry about the warning, IIRC you would still have active handling (if you wanted it on) based on the previous calibration. Can anyone confirm this?
To me it would make no sense for GM to COMPLETELY DISABLE ah each and every start until this small calibration is completed.
10-30-2014, 01:41 PM
#9
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But don't worry about the warning, IIRC you would still have active handling (if you wanted it on) based on the previous calibration. Can anyone confirm this?
To me it would make no sense for GM to COMPLETELY DISABLE ah each and every start until this small calibration is completed.
The reason they do this is to account for wear in the steering assembly. As the assembly wears the straight ahead positioning of the steering shaft can change so they want to make sure the calibration relates to the current state of the car.
Bill
10-30-2014, 02:28 PM
#10
Race Director
Basically, it is disabled until the calibration is complete. Under normal circumstances the calibration takes place within a few hundred feet/seconds of leaving the location where the engine start occurred. If you are in a parking lot driving to the exit and are making a number of tight turns before the system calibrates you can get the same message.
The reason they do this is to account for wear in the steering assembly. As the assembly wears the straight ahead positioning of the steering shaft can change so they want to make sure the calibration relates to the current state of the car.
Bill
The reason they do this is to account for wear in the steering assembly. As the assembly wears the straight ahead positioning of the steering shaft can change so they want to make sure the calibration relates to the current state of the car.
Bill
10-30-2014, 10:12 PM
#12
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It all depends on how long it takes for the steering sensor to stop turning and 4 all 4 wheel speeds to indicate the car is going straight. As soon as that happens the system calibrates. If the steering is straight then both front wheels have to be traveling the same speed and both rear wheels have to be traveling the same speed and within the correct ratio with the front wheels. I imagine changing tire diameter relationships from front to rear impacts the time it takes to calibrate. If the rear tires are spinning as when you launch in an autocross you might reach the first turn before the conditions are met. Then on other runs the tires don't spin as much and you don't get the calibration warning. A lot of autocross course designers put a sharp turn within 50 or 60 ft of the start line.
Bill
Bill
10-30-2014, 11:04 PM
#13
Race Director
It all depends on how long it takes for the steering sensor to stop turning and 4 all 4 wheel speeds to indicate the car is going straight. As soon as that happens the system calibrates. If the steering is straight then both front wheels have to be traveling the same speed and both rear wheels have to be traveling the same speed and within the correct ratio with the front wheels. I imagine changing tire diameter relationships from front to rear impacts the time it takes to calibrate. If the rear tires are spinning as when you launch in an autocross you might reach the first turn before the conditions are met. Then on other runs the tires don't spin as much and you don't get the calibration warning. A lot of autocross course designers put a sharp turn within 50 or 60 ft of the start line.
Bill
Bill
