Ducman69

I did a search but it came up with multiple pages which didn't really address this basic question... how does the active handling system work?

Does Active Handling use the same sensors that monitor the tire pressure? If they do, these are no longer on the car due to the aftermarket wheels.

The reason I ask is that I have no codes or errors regarding the traction control and/or active handling and they are confirmed to both be turned on, but when playing around to test the limits of the suspension I was able to initiate a power-slide w/o issue. I was under the impression that the traction control and active handling should have kicked in to prevent this.

2001 C5.

bsmith

has nothing to do with tire pressure sensors.

I dont know the specifics, but I think it works with the wheel speed sensors that are part of the ABS system though.
I can break loose the rear end a little before TCS kicks in... but not that much...

PDXBigMan

It does not use tire pressure monitors. Uses ABS, wheel spin sensors, and yaw sensor.

QuikZilver

Active Handling does not use the tire pressure sensors. There are speed sensors on all 4 wheels. I believe there are some other sensors as well. I don't know if power-sliding is supposed to not happen with the Active Handling or not. Being a 2001, you do have the Active Handling II software on your ECU.

tpocock

Nope, tire pressure sensors are completely different.
ZO6 does not have tire sensors but does have active handling.
Active handling uses each wheel's speed sensor, steering wheel position sensor, & accelerometer to determine when you are understeering or oversteering, and applies ABS on the appropriate individual wheel to bring you back onto the desire path.

Vetteman Jack

No, the tire pressure sensors are not used. There are many other sensors at play with the active handling sytem though.

CAJUNY2KC5

If you have it, the video that comes with the car has a good explanation in it as does some of the sales literature.

Ducman69

Well, I'm going to wait till the next time it rains and I'll have to take her out to a wet parking lot and learn the limits and balance of the vehicle with it on and off. Perhaps the system was aiding me in controlling the power-slide, and I just didn't realize it as I am new to Vettes... it definitely wasn't a full out drift as there wasn't sufficient room.

Out of curiosity, are there any flashing lights when it engages?

CAJUNY2KC5

Yes. You'll get a DIC message - Active Handling Engaged

Zilla

Here is a article regarding how activate handle works.

What Active Handling Does
The Active Handling system activates when there is a significant difference between how the driver intends for the car to corner and how the car is actually cornering. Working together with the ABS and traction control systems as needed, it automatically applies any of the four brakes to help correct the situation .

A real-world example of this might be a sudden lane change on a wet road surface to avoid a unexpected hazard -- like a huge pothole.

Faced with that scenario, many drivers may turn the wheel abruptly to the left to avoid the pothole. That input, combined with the reduced traction available, could exceed the limits of traction available to the front tires, and a condition called "understeer" could make itself apparent. In an understeer situation the car tends to plow straight ahead -- not at all what the driver may want it to do.

In this scenario, Active Handling will work to help correct the car's understeering behavior by automatically applying the left side rear brake, helping to "pull" the car into the left turn.

Once the car is in the left lane, the driver tries to straighten it out, but the car's yaw inertia could cause it to turn even more than the driver wants it to, and a condition called "oversteer" could come into play. That's when the car's rear wheels lose traction and the back of the car starts to swing around.

Active Handling should once again sense that the car is doing something that the driver doesn't intend, and it will work to help correct it by, in this case, applying the left side front brake. The resulting torque tends to straighten the car.

Depending on vehicle speed, and the traction available, the car could continue to be influenced by the "whipping" motions that the first two steering inputs created, so a few more steering wheel movements may be required to settle it down -- and Active Handling will continue to apply individual brakes as necessary to assist the driver in maintaining control.

In another scenario a driver could find that he's entered a turn too aggressively, thereby setting up similar understeer and oversteer conditions. Once again, Active Handling would react to the conditions and work to help bring the vehicle back into control by selectively (and automatically) applying the car's brakes as needed. How Does It Do That?

Active Handling uses a simple yet sophisticated system of sensors to detect unwanted vehicle manuevers. These sensors include a steering angle sensor, yaw-rate sensor, lateral accelerometer and sensors in the vehicle's ABS brake and traction control systems. All of the data that these sensors provide is fed into the Corvette's onboard computer where specially-developed software "reads" all of the inputs and automatically activates the car's brakes selectively to help the driver bring the vehicle back under control.

Steering Angle Sensor: This digital sensor monitors the driver's steering inputs immediately and communicates the steering angle that the driver has selected back to the system. It is accurate to within one degree of steering angle change and is located in the car's steering column.

Yaw-Rate Sensor: This solid-state device utilizes a tiny pair of ceramic tuning forks to measure the actual rate that the car is turning or yawing from the centerline. This data is continuously fed into the Corvette's computer where the yaw rate is compared to the steering angle. Any variation beyond a pre-programmed set of values will result in activation of the Active Handling system's assist features. The yaw-rate sensor on the Corvette is located inside the center console.

Lateral Accelerometer: The lateral acceleration sensor measures the centrifugal force created in a turn. The data it provides is weighed against all of the other inputs and is used to calculate whether or not the car's limits are being exceeded for the speed and traction conditions that exist. This sensor is located beneath the passenger seat.

Unique Controller & Software: All of the information being provided by the sensors mentioned above is processed by the Corvette Active Handling system's computer through a very sophisticated and specialized software package. This computer is actively linked to the ABS brake system and the traction control system -- all these systems share information continuously. This multiple linkage is vital because the combined inputs from each system make the fully-integrated system better able to respond to a wider variety of inputs from the driver.

During the 1998 model year, just prior to production of cars with the Active Handling option, the Corvette's ABS brake hydraulic control unit will be relocated to the front of the engine compartment to facilitate quicker Active Handling system "warm-up" and shorten front brake response time when the brake fluid is cold. In temperatures below 14oF, the Corvette's Driver Information Center (DIC) will display an "Active Handling Warming Up" message as soon as the vehicle reaches 6-mph. That's a caution to the driver that Active Handling is not fully-functional yet. As soon as the system warms up, another message "Active Handling Warmed Up" will be sent to the driver via the DIC.

Competitive Driving Mode
The Corvette Active Handling system will be the first of its type to offer dual mode operation. In addition to an "OFF" mode, in which Active Handling is disabled, the system also allows the driver to select a "COMPETITIVE DRIVING" mode for autocross or gymkhana competitions. In this mode, the Active Handling system remains fully-functional -- measuring steering, yaw rate and lateral acceleration inputs as well as applying individual wheel brakes as required -- but the traction control system is disabled, allowing for some wheelspin and oversteer that skilled drivers often find beneficial in competitive driving.

Summary of Active Handling System Modes

ON - Active Handling is automatically enabled when the car is started. This is also true of the ABS brake and traction control systems.


OFF - Like traction control, the Active Handling system may be manually turned off if the driver so desires. This is not true of the ABS brake system which is always enabled.


COMPETITIVE DRIVING - In this mode, Active Handling and ABS are both enabled, but traction control is shut off.
The "OFF" and "COMPETITIVE DRIVING" modes are important features on a high-performance sports car like the Corvette. As mentioned earlier, skilled drivers may find that some wheelspin and oversteer can be beneficial to their lap times in competitive events, and the Corvette system allows them to operate the car in this fashion when appropriate. Chevrolet recommends against selecting these modes for street use.

Limitations
The overall effectiveness of the Corvette Active Handling system, or any similar system, is directly related to available tire traction and the aggressiveness of a given maneuver. Active Handling is designed to work to use existing traction to assist the driver -- but it cannot overcome the laws of physics. The Active Handling system reacts only in extreme situations, and special care should be taken when the system does activate because it's a clear signal that vehicle or tire limits are being exceeded

MagikDraggin

The previous post mentions a condition where the active handling can be left on, while the traction control is turned off.

How exactly is this accomplished, as with my '04, I only have a single button and pushing it, either turns all handling/traction systems on or off, there is no "half and half" option.

I do recall someone mentioning that this can be done by hitting the "reset button" at some particular time and that will do it......but I can't figure that out either.

Can someone please explain to this dummy, just how that is supposed to work?

RockyL32

press and hold active handling button for about 5 seconds DIC will say "competitive driving" active handling will be on and traction control will be off

Zilla

To turn off the traction control but still have the active handle on is very easy and since you have an '04 this can be while stopped or moving. All you need to do is press the active handling button down for 5 seconds and after 5 seconds, the system should be in Competitive Driving and it should be displayed on DIC. Once in the Competitive Driving mode the traction control is turned off and activity handle is on.

Hopefully this will clear things up

MagikDraggin

Thanks to both you and Rocky L32......yes, it makes perfect sense now. And it works!