DIC messages today
Thread Starter
Le Mans Master
Joined: Oct 2005
Posts: 7,281
Likes: 443
From: Texas Where God intended me to be.
2023 Corvette of the Year Finalist - Unmodified
2022 C5 of the Year Winner - Unmodified
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St. Jude Donor '08 thru '11,'22 thru '26
DIC messages today
So the wife was driving the Vette to work today and these messages popped up on the DIC 
Service vehicle soon
Service active handling soon
Service traction soon
Since I’m not there to check things out any reason for them to all come up at the same time? She has around 75K on her
Service vehicle soon
Service active handling soon
Service traction soon
Since I’m not there to check things out any reason for them to all come up at the same time? She has around 75K on her
Thread Starter
Le Mans Master
Joined: Oct 2005
Posts: 7,281
Likes: 443
From: Texas Where God intended me to be.
2023 Corvette of the Year Finalist - Unmodified
2022 C5 of the Year Winner - Unmodified
Cruise-In X Veteran
St. Jude Donor '08 thru '11,'22 thru '26
Tech Contributor
Joined: Dec 2003
Posts: 19,384
Likes: 87
From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
This explains the active handling system. When it detects a fault it trips and throws those captions on the DIC. If you look at the codes it will tell you which part of the AH is causing the trip. It could be EBCM, BPMV sensors or grounds. If that was Greek to you I can explain further. First thing is to run the onboard diagnostics and post them up. Then we can troubleshoot.
Its no problem if you run the car without AH. Just dont drive it hard as you lose the protection the system gives you.
Active Handling System
The following text appeared in a GM Press Release that was issued at the Las Vegas SEMA Show in the Fall of 1998. The Active Handling System, RPO JL4, debuted on the 1998 Corvette and became standard equipment on the 2001 model.
________________________________________
The Corvette Active Handling system is a logical next step in the evolution of enhanced chassis control systems like ABS brakes and traction control. Working in close concert with those other two systems, Active Handling enhances the accident avoidance capabilities of the already nimble Corvette. It will be offered as an option (JL4) on all 1998-1/2 Corvette models. Additionally, it will be a required option on replicas of the '98 Corvette convertible Indy 500 Pace Car.
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.
Its no problem if you run the car without AH. Just dont drive it hard as you lose the protection the system gives you.
Active Handling System
The following text appeared in a GM Press Release that was issued at the Las Vegas SEMA Show in the Fall of 1998. The Active Handling System, RPO JL4, debuted on the 1998 Corvette and became standard equipment on the 2001 model.
________________________________________
The Corvette Active Handling system is a logical next step in the evolution of enhanced chassis control systems like ABS brakes and traction control. Working in close concert with those other two systems, Active Handling enhances the accident avoidance capabilities of the already nimble Corvette. It will be offered as an option (JL4) on all 1998-1/2 Corvette models. Additionally, it will be a required option on replicas of the '98 Corvette convertible Indy 500 Pace Car.
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.
Last edited by DeeGee; Sep 29, 2009 at 03:45 PM.
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
I cut/paste this from another thread...
Here is how to pull codes on the DIC:
How to Pull Codes:
1. Turn your key to the "ON" position, but do not start the engine.
2. Clear any present messages by pressing the RESET button.
3. Hold the OPTIONS button down, and press the FUEL button 4 times. (This will get you into the "codes" section of the DIC.
4. The computer will automatically display all the codes your car has created. It will cycle through each code every 3 seconds. (Have a pen and paper handy to write down the codes)
Note: Any code that ends in an "H" is a history code (something that has occurred in the past, but is not reporting as an error currently.)
5. Once the computer has finished going through all of its codes, press RESET to enter Manual Configuration mode. It should start with a module and show "NO CODES" or "# Codes."
6. To optionally reset codes once in manual mode, press and hold RESET until is displays "NO CODES."
7. Press OPTIONS to go into the next module (ie, from PCM, or Powertrain Control Module, to TCS, or Traction Control System.)
8. Repeat Step 6 until you have reset all the codes in all the computer modules.
Note: Only reset the codes if you want to- it is not necessary to reset them every time you pull the codes.
9. When finished, simply take your key out of the ignition.
Once your wife (or someone else) pulls the codes, they should list them here. An "H" means history and a "C" means current. The latter are the ones that should be addressed and rectified.
Once the codes are identified, then they can be deciphered at this site...
http://www.stengel.net/diccodes.htm
Then you'll have an idea on how to proceed...
Here is how to pull codes on the DIC:
How to Pull Codes:
1. Turn your key to the "ON" position, but do not start the engine.
2. Clear any present messages by pressing the RESET button.
3. Hold the OPTIONS button down, and press the FUEL button 4 times. (This will get you into the "codes" section of the DIC.
4. The computer will automatically display all the codes your car has created. It will cycle through each code every 3 seconds. (Have a pen and paper handy to write down the codes)
Note: Any code that ends in an "H" is a history code (something that has occurred in the past, but is not reporting as an error currently.)
5. Once the computer has finished going through all of its codes, press RESET to enter Manual Configuration mode. It should start with a module and show "NO CODES" or "# Codes."
6. To optionally reset codes once in manual mode, press and hold RESET until is displays "NO CODES."
7. Press OPTIONS to go into the next module (ie, from PCM, or Powertrain Control Module, to TCS, or Traction Control System.)
8. Repeat Step 6 until you have reset all the codes in all the computer modules.
Note: Only reset the codes if you want to- it is not necessary to reset them every time you pull the codes.
9. When finished, simply take your key out of the ignition.
Once your wife (or someone else) pulls the codes, they should list them here. An "H" means history and a "C" means current. The latter are the ones that should be addressed and rectified.
Once the codes are identified, then they can be deciphered at this site...
http://www.stengel.net/diccodes.htm
Then you'll have an idea on how to proceed...
Thread Starter
Le Mans Master
Joined: Oct 2005
Posts: 7,281
Likes: 443
From: Texas Where God intended me to be.
2023 Corvette of the Year Finalist - Unmodified
2022 C5 of the Year Winner - Unmodified
Cruise-In X Veteran
St. Jude Donor '08 thru '11,'22 thru '26
thanks guys.
I've pulled codes before for other reasons but I'll see if i can't get someone in the San Antonio area to pull the codes for me. She doesn't drive it hard at all since she is afraid of it.
I've pulled codes before for other reasons but I'll see if i can't get someone in the San Antonio area to pull the codes for me. She doesn't drive it hard at all since she is afraid of it.
Last edited by Burnt C6; Sep 29, 2009 at 04:07 PM.
