Went autocrossing last Sunday. Nephew and I had 4 70-sec runs each and ran 1st run with Competitive Driving on and the last three with traction control off. No issues during runs. On my way home however, the Service Active Handling, Traction Control and ABS lights and DIC messages came on. I did not feel any issues on my way home on a 15 mile winding road but the lights stayed on. Parked the car on my driveway to unload my cooler and race stuff and when I re-started the Service lights were off. The next day I moved the Vette around to change out of the Nitto NT-01 race tires and the Service lights came on again. Hit re-set which removed it from the DIC display but the icon lights stayed on. Any ideas to what the issues are? I have run the same set-up several events without the Service lights coming on.

Car specs: 2001 M6, F45, C6 Z51 front sway bar, metal end links, lowered on stock bolts, Nitto NT-01 tires.

Update: Drove the Vette to work and the DIC messages (service active handling, traction control and ABS) came on at start up and at shut down. Driving around at legal speeds the car did not display any weird handling nor did the ABS seem out of wack. So I went autocrossing again last Sunday. DIC messages went on before my first run which I took more carefully than I usually do (I get up to speed fairly fast). When I started back up for my 2nd run none of the prior DIC messages came on and never came back on after all my runs and on the way home. And everything seemed to be working fine. Drove it another time this week and did not get any DIC messages. Can't believe that everything is fine; I haven't tried seeing what codes are still there. I'll get those this weekend. P.S. Happy 4th!!!

 

Mine does this a lot too. Just a very temperamental system from what Ive seen. Happens off and one over the years. Im no help as to why. But it doesnt ever seem like a serious issue.

 

Fairly sure it's the race tires causing the issue.

 

I was also going to speculate it was the tires, but didn't want to post my thoughts, as it was only a guess, because of my skill level.

Still, the only variable effecting the system is the tires, unless something is broken. Perhaps the stagger got worn at the track, enough to freak out the computer. Or it could be the electronics are just weak in that system, as another posted. My active handling has given inconsistent displays at times when I play with the settings, I just assumed it was looking for more speed and didn't understand someone just playing around to explore the system.

I'm cautious of the stuff. A guy at work had a brand new Ram truck that decided to lock up the rear brakes and spin his son across four lanes of freeway , luckily no injuries .

 

Stock sized 245/45/17 front; 275/40/18 rear. Correct stagger for the C5. Been running this tire Nitto NT-01 for 3 years with a new set two events ago.

My co-driver and I have really started to drive the Vette hard with this tire including hard braking and driving with the nannies turned off. While I realize the Z51 suspension is probably better than the F45 Selective Ride not ready to removed the F45 at this time ($$$).

 

When you said "hard braking" my first thought was the ABS EBCM has bit the dust. 8VETTE7 is correct, you must pull the codes before wasting any more time speculating.

Good luck and if it is the EBCM you indeed have a problem.

OBD

 

Here are the codes:

28 - TCS 5 codes
C1214 H C
C1221 H
C1222 H
C1236 H
C1248 H

60-IPC
B0521 H

AO-LDCM
B2282 H
B2284 H
U1064 H

A1-RDCM
B2283 H
B2285 H
U1064 H

BO-RFA
U1064 H

I see only one "Current" while all the others are "History". So what do all these mean? Could the race tires because of the higher traction overwhelm TC and ABS with higher "G's"? Can I reset to remove the displays? HELP!!!

 

1214 is the EBCM relay. absfixer.com can fix this for $150.

 

So what happened to the relay? What caused it to go bad?

 

I believe the common cause is the soldering on the circuit board heats up and the relay no longer makes contact with the circuit board. This happened to me after a track day. If you are feeling up to fixing it yourself you, and have a soldering iron you can probably fix it for about 15 cents worth of solder. Or the relay could have failed which costs about a dollar. Just be careful pulling the module off the abs pump. and if you are opening it up to fix it yourself, be careful pulling it apart as you can break some very small wires inside of it and have to buy a new module.

corvetteforum.com/c5-tech/2816125-how-to-repair-ebcm-avoiding-costly-repairs-through-absfixer-or-fleabay.html