Not really. Here are the exact words in the Owner's Manual. As you can see, when in "Competitive Driving" mode, the traction control system is disabled, but the active handling system and anti-lock brake system is still active.

To turn it ALL off you need to make sure it says "TRAC/ACT HNDLG - OFF" on the DIC. The anti-lock brakes will ALWAYS be active, no matter what mode you are in.

TRAC/ACT HNDLG - ON: If the Traction Control
and Active Handling Systems are off, depressing the
Active Handling System console button momentarily
will turn both systems on. The message TRAC/ACT
HNDLG - ON will be displayed temporarily in the DIC,
the instrument panel cluster light will be off and a chime
will sound.

TRAC/ACT HNDLG - OFF: By pressing the Active
Handling System console button briefly, the driver can
turn the Traction Control and Active Handling Systems
off. The message TRAC/ACT HNDLG - OFF will
be displayed in the DIC, the instrument panel cluster
light will be on and a chime will sound. You can
acknowledge this message by pressing the RESET
button. The anti-lock brake systems remains on with
the Traction Control and Active Handling Systems off.
You should adjust your driving accordingly.

COMPETITIVE DRIVING: When the Competitive
Driving mode is selected, this message will be displayed
in the DIC. The instrument panel cluster light will not
be on when the Competitive Driving mode is selected.
The Traction Control System will not be operating while
in the Competitive Driving mode. You should adjust
your driving accordingly.

 

You did see the letter in Post #103 above from GM on this, right? They specifically said of the yaw rate sensor mounting is loose and vibrates that it can cause the AH system to misbehave.

 

WOW, thanks for the heads up on that and sorry to give misinformation. After further research I found a GM article on it too. It is 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.


--------------------------------------------------------------------------------
Go to the link to read the entire thing. It explains what the Steering Angle Sensor, Yaw-Rate Sensor, Lateral Accelerometer and Unique Controller & Software do.

http://corvetteactioncenter.com/tech...ehandling.html

 

Yeah, but you do realize that if any of those sensors give a bad/flaky input signal into the computer that it can cause the system to glitch out and potentially cause a problem like some of there guys have described. Bad enough that it could cause a tire to lock up and pull the car off the road as some that had this experience have described.

GM even says in their letter that:

"Some vehicles may have a concern with intermittent unwanted activation of the Active Handling System. The Yaw Rate sensor signal can usually be verified to be changing at the time this occurs. DTC C1282 will likely be present in the ABS module."

 

[QUOTE=Johnz02Z06;1584651258]If you hold down the "active handling" button 10 seconds or so you will then be in "competitive driving" mode with no assist at all from the car (NO traction control, NO active handling and NO ABS)

Wrong; selecting Competitive Driving Mode only disables the Active Handling System and Traction Control. You cannot disable ABS as you described.

 

WRONG! turns of TC but not AH. Just a quick press of the button turns off both the TC and AH. ABS is never disabled.


Why don't you post correct information?

I didn't even read it all yet I saw this post. Try the bottom of the first paragraph. On another note. You need to do this on every newer car you own. They all have AH nowadays. The C5 isn't the only vehicle that could have this issue.


http://forums.corvetteforum.com/1584635183-post81.html

If you don't like that one, you could read this one.

http://forums.corvetteforum.com/1584638747-post84.html


Finally, the system is supposed to apply the brakes to help steer the vehicle but it should never just lock a wheel up. That would be a retardedly stupid system design because a locked wheel has no steering ability. The AH would apply the brakes but the ABS part of the firmware should release enough to prevent a lockup from happening.

 

[QUOTE=Dobbinshabby;1584645717]I actually had someone pull out in front of me on a rainy day and wasnt able to stop because my ebcm failed months ago and I couldn't find a new one.

My tires were locked up FOREVER.

Sorry to see your car messed up but I don't think that the EBCM can disable ABS either while it's functioning properly or if it fails. EBCM only applies line pressure to individual brakes and I don't think that it by-passes ABS. Also ABS only "HELPS" prevent a skid while there is some traction. Ones you're skidding or hydroplaning ABS has little or no effect.

IMO

 

[QUOTE=OneCylinder;1584652985]I was not intending to sound like a jerk when I asked:
"Why not just answer the guys question if you know the answer??"

Thank you to all on this post for sharing your knowledge on this subject. My EBCM stopped working a year ago and has not been a big deal to me and that is why I have not "fixed" it. I know it is a great thing to have when it is working correctly which I am betting it does most of the time. I also betting it has saved many more people from an accident than it has caused.
I do not plan on fixing mine.

 

[I do not plan on fixing mine.[/QUOTE]

I'm no expert but if you don't plan on fixing or using the EBCM I would suggest that you professionally have the EBCM system completely isolated (removed) from your ABS since the EBCM is plumbed into your master cylinder. Your brake fluid is travelling through a manifold on the EBCM; a module that as you stated is not functioning properly and not being monitored.

 

hi can you please tell me where i can find this document i needed for my lawyer because the same thing has happended to me but i eneded up hitting a person sitting on the bus stop and he passed away after couple days of the accident so my lawyer has to asked me to find any info i can that can prove that this can happen to C5.

 

I would think your local dealer may be able to print it for you. I would not tell them why. If not then I would find a mechanic you trust and they should be able to get it. I just called my mechanic and he will see if he can pull it up.

 

My left front brake locked up while going 5mph. it stopped and I tried to go again and it kept locking up. I saw the display on so I switched the active handling off. I took it to the dealer and they recommended no repairs. I switch it off every time I start the car because it lock up a few minutes later. I haven't had time to read all the post but it sounds like a problem a lot of cars are having. I got a letter from NTSA to fill out after calling them. The dealer never mentioned that the brakes we locking up in his report only that the message went on.

 

I read in a previous thread "Active Handling almost Caused a Wreck Today"

http://forums.corvetteforum.com/c5-g...ed+wreck+today

that according to GM engineers the only way to permanently disable AH is to disconnect the steering wheel position sensor SWPS and that this will still retain the ABS and TC.

Also check this thread

http://forums.corvetteforum.com/auto...ne-c5-z06.html


Answer for how to kill AH from 2nd page of said autocross discussion in above link

Quote:
If you put the wires going to the SWPS through a switch you could turn the AH on and off at your pleasure.

So if your car is acting up mysteriously applying the front brake left or right this may be a solution except you will have a DIC code which you can cover with a piece of electrical tape.
Also the grounds on the frame on either side near the front of the engine can get corroded leading to ABS AH issues



Mine were clean but you can see the green starting to form on a few pins and the eye.
I only have 24k miles on my car but as a precaution
I cut them out and soldered the wires to car stereo ground eye rings and bolted those to the chassis.
I also have a Big 3 kit for my 1100 watt rms stereo and it adds an extra large ground cable between the engine and chassis right where the passenger side ground I cut out is.

 

The only time I crashed mine was on a cruise with several other vettes.
There was a little straight road and lots of guys were showing off.
I did the same and at the same time my traction control light and ABS lights came on and my gas pedal was hung wide open. It was hit a innocent Vette in the rear or run through a fence into a just plowed field that was mud because it had been raining for 2 days
It sunk up to the doors and when it stopped the wheels were still turning. I killed the engine and blamed myself because I had been cleaning the car and had the area where the TC button is off and have stainless steel mats. I thought the gas was hung in the mat and the TC was because I had not attached the plug securely but was never positive.
75% of the damage to the car was done pulling it out of the mud which ripped the front clip and fenders apart.
They were going to tow it with a normal wrecker because their flatbed was on another call.
I told him to get it into the road and unhook it.
I pulled all the parts that were loose odd. raised the headlights by hand because they were in a bind and the motor would not move them. I drove it 50+ miles home, the 1st 20 were not fun because mud was flying everywhere. After the mud was finally off the tires it ran fine. There was n frame damage at all only cosmetic. It drove straight as an arrow with no hands on the wheel. I took it to a State farm recommended shop
Gold Team auto paint and body
They wanted to total it right away without looking at it (red flag) which was crazy. The broke body parts bolt on and off.
I got it back and the alignment was all go heck I drove it to them and it was perfect. They put the center air dam on backwards I told them when I picked it up, they said bring it back next week, It lasted less than 50 miles. They has used a wire brush to clean the wheels which ruined the chrome. They removed my working switchback LEDs and put the front parking / turn bulbs in so they were hitting the top and melted the housing.
I took it back 6 times, the last time they told me they were finished not to come back after being paid over $17,000 3 months later the paint started flaking off the fender The adjuster came and looked at it and told me to take it to another shop which was a ford dealer. They fixed everything within 3 days. the original shop had to pay the new shop to repair it and get me a rental.


Off my rant the more I thought about it the more I believed that it may have been a problem with the car but could never prove anything. It now has300,000 plus on it and there has not been any problems since so it was most likely driver error but I will never
be sure.

 

Correct me if I'm wrong. We have a 30 year old, with many years of experience driving out of 1000's of oversteer conditions, driving a car he's owned for the long time of a week, entering a hiway in 4th gear at a safe speed of 70mph. Yet somehow the car "hit the ditch going backwards, then flipped and tumbled for over
200 feet! It took out about 150 feet of fence and guardrail before coming to a stop, and
this was all after he skid across three lanes..."

Is that the story he's sticking with? If you can't convince the forum he didn't lose control it'll never fly in court.

I've blown front tires in excess of 70mph and still managed to get stopped before crossing into on coming traffic. I've had rear axle shafts come out at 70mph and pass me, yet I still shut down safely. I spent 15 years in the towing and repo business and when a car hits fence and guardrail they stop pretty fast at 70mph and don't need a 200' debris field to get stopped. You're not going to take out 150' of fence and guardrail after skidding across three lanes leaving black marks driving 70. The black marks will scrub speed unless they were straight, as in a xcelleration marks.

Another bit of info that sticks out is the statement that at 70 in a Z traction isn't an issue. In my non z I can easily break the tires loose at 70 in 4th gear.

 

All fishiness from the original story aside, I had something similar happen on my 2002 Escalade the other day. I had a Service Stability message and the code indicated a bad steering position sensor so I replaced it.

Leaving the shop on my test drive after installing the SWP sensor, I had the Tech 2 plugged in. Running about 65 mph, the truck pulled HARD to the left and immediately gave a SSS message and then a Stability System Disabled message. The code is now showing it needs a Brake Pressure Differential Switch replaced.

While I think the extent of the original wreck in this thread indicates far more than 70mph, I don't think it's unreasonable to say that a faulty AH system can cause you to almost unavoidably crash....

 

I drove my 2001 with it disabled before I got it fixed.You just have to take it easy.I hade no problem.

 

 

I shopped for 6 months before finding a 1998 that did not have AH option installed. I was aware of the claims by some of uncontrilled behaviour and never wanted to be part of that. In 1999, AH became standard, all Vetts have it installed, so I had so shop ONLY for a '97 [ no AH] or a '98 [ AH as an option ]. As it turned out, I still had problems with some of vehicle aids, even with no AH. I had 3 seperate occasions where the anti-lock brake system defeated the brakes at less than 4 mile per hour in stop and go traffic. ONLY the action of STANDING on the brake pedal with BOTH LEGS at as much pressure as I could muster over-rode the ABS and allowed me to stop short of rear ending the car in front. THAT was enough for me. I defeated the ABS and have for 6 years been driving incident free, having total human control over the braking sytem. I am sure that no one could come up with enough evidence to deal with a court case, but THINGS DO happen with the ABS and AH systems on these cars. A fellow in the club I used to belong to suffered an AH failure on a puddled freeway. The system got confused about the puddles that came with a downpour, ...threw his C5 180 degrees around and into a guard-rail at about 70MPH, tearing off the entire right side of the car, and nearly killing his significant other....she spent 2 or 3 months in the hospital, and was never the same after the injury.

In my own car, I will eventually take the ABS removal a step beyond 'disabled'....I will be installing a Tilton dual master cylinder system with a balance bar. Standard fare in race cars, 100% reliable, and totally predictable....plus, the front to rear brake ratio is adjustable.

From what I know now, any year Corvette with AH can be electrically defeated and real manual control brakes restored. My next C5 can be any year....because the brakes will become 100% manual controi the day I pick it up. ...perhaps even before I drive it home!

BE SAFE!

 

Don't hammer yourself for this....what you describe is classic failure mode for these and most other modern cars, equipped with modern engine/vehicle managment computer systems...Throttle is computer controlled, -fly-by-wire and when the computer gets messed up, all H*** can break loose. The syetems are dependant on ALL sensors working correctly, ALL connections in the harnesses to be 100% proper, and the electronics themselves to be free of solder failures, tin whisker development and other things can can plague processors like firm ware bugs and memory glitches...