This issue is somewhat in depth....and I could use some STRONG TECHNICAL support regarding the layout of VSES.


2005 C6. Car was BONE stock when I recieved it, with no known issues what so ever.

I installed Kooks 1 7/8 headers
Kooks 3 inch X pipe (off road)
B&B bullets
B&M shifter
and PCM calibration (tube)

My problem is, at WOT, usually at around 88-89mph, the active handling will come on, activating the right front brake mostly, as well as the other 3 brakes. The right front is the most noticable, as the car will violently jerk to the right. It feels like the car hits a patch of water or something, to give you an idea. It should be noted that if you turn active handling and traction control off, these issues DO NOT occur.

I did some testing with my TECH II....and I recorded a snapshot from 14mph to 90 or soo mph, or whenevr the fault occured. I have all GM documents to follow. The car DID set a C0196 code. I followed document ID# 1460389 in the GM technical service manual, and followed the recommend flow chart.

The chart recommends that I check the voltage at the YAW rate sensor input. It requires a range of .015v(volts) to 4.85v. The car actually had 2.5v, which is more then in range. Next step, is to record the yaw rate sensor input paramater, which is also with the specified range of 2.3v and 2.7 v. I am actually recording again, 2.5 v.

The next step it tells me is to follow DIAGNOSTIC AIDS. Thats it. So, I recorded the snap shot...and this is what I recieved.

At 85mph.....and no fault at all

YAW sensor 0.6 degree's per second
YAW signal 2.5v
Lateral accel 2.5v
Lateral accel -.02g
SWPS A 2.06v
SWPS B 0.41v
Steering sensor -1
Steering centered- yes
VSES active- NO

at 89mph when the FAULT OCCURED

YAW sensor -74.7 degrees per second
YAW rate 0.5v
Lateral accel signal 2.5v
Lateral accel -o.o4g
SWPS a 2.02V
SWPS B 0.45v
Steering sensor -2
Steering center YES
VSES ACTIVE- YES

Soo....as I was baffled....I called my GM tech support line. They where pleased with the amount of info that I gave them....but, non of what I was telling him sounded like anything similar to a past vehicle that they have helped to diagnose in there records.

After talking with the gentleman for a while....he advised me to replace the YAW sensor. Which I did. 5 minutes ago, I went for a WOT test run....and sure enough....it still activates. It has not set a code as of yet but, its there.


Other then a wireing failure, I'm kinda at a loss for words to how to fix this problem. After the diagnoses that I have done on the car, I am now certain it is nothing that I did to have caused this fault. Atleast nothing that I can see on the surface.

Has anyone here had this problem? Anything similar? I'd appreciate any help, or any expierences that you may have had that were similar, and ths soultion to the problem that you had. It's a good friend of mines car, and I really want to help him out.....i'm just getting backed into a corner here.

Thanks for ANY help that you can supply me with.

Jamie

 

Well, you can see the YAW rate is skewed at 89mph and you have a new YAW sensor installed. I would lean towards the EBCM as the problem especially since it's related to vehicle speed. I wouldn't think it could be a wiring or pin contact issue because of the speed again. Just for grins, have you checked what the speed sensors look like at 88-89? You may need to plot them to see a 'blip' or spike in the speed.

 

i know this will sound unrelated but how are your tire pressure sensors ?
something seems to be throwing off the YAW sensor.

what happens if you slowly get up to speed, does it still trigger the event ?

 

Thanks for reply, I appreciate it.

I failed to mention that when I performed this snapshot, it also records the wheel speed sensors, which were all sweeping seemingly well. The rear speeds where no more then 1 to 2 mph higher then the front wheels at any time. When the VSES went active, things did change a little, since it was activating the brakes. For example, the vehcile speed would be at an indicated 88mph, and the sensors would read...LF 88mph RF 89mph LR 90mph RR 90mph when activated.

Under accel without the fault, it would be an indicated 85mph...LF reads 85mph RF 86mph LR 87mph RR 87mph

with VSES active at an indicated 91 mph LF 91 RF 90 LR 93mph RR 93mph

soo...I need to look at the specs of how much allowance in MPH variation I am allowed to have between each sensor.

I have had EBCM issues with other GM vechicles....which resulted in re-wireing with NEW pins to to insuficent pin tension. This problem does seem different.

I'll have to look into the ebcm more I guess.

Thank you again for your input.

Jamie

 

I agree, good idea. I thought of this the first time it triggered. I looked at the sensors on the DIC and two were under 30psi. So, I added air...and re-tested,...no change to my dissapointment.


This morning, I used your idea, and layed into the throttle smoothly,.....I got well past 120mph without any issues whatsoever, and no active handling light came on. So, it seems that WOT is the only way to trip it, seemingly.

The search continues.

Thank you for your input as well.

J

 

found a document ID 1831892 for 2006 vettes.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

SERVICE VME
This is a service VME to all Chevrolet Dealers regarding 2006 Chevrolet Corvettes with an active handling light or message. Some owners may note an intermittent active handling light and message on the DIC. This is a normal occurrence when the active handling system is operating and no repairs are required. If the Service Active Handling message is displayed a DTC will generally be stored and the vehicle will require service. Most complaints advise that code C0710 is stored. Bulletin 06-02-35-002 was released to advise dealerships where to inspect the harness and connection that could be the root cause of the concern. When the telescopic steering column is fully extended it may stress the connection at the sensor and make an intermittent connection. Before replacing a steering wheel position sensor, part number 15231656, check the harness as outlined in the bulletin. If the harness is too tight please contact Art Spong at 586-*** *** and provide a product report so the root cause can be determined.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.


Which I visually inspected....will look more into this today.

 

i would go ahead and perform the work for the steering wheel wiring harness.

if/when you find it and do it would you mind posting some pics. i stuck my head down there and couldn't find anything.

 

I looked at this last night.....and didn't see any VISUAL failures.... but, I have no choice but to perform the diag for this. I'll keep u posted. I am limited to time, as i'm doing this on the side.....and I other dealership wokr to do.... but I will try with the pictures.

Thanks man.

J

 

...and I tested this thing again, without a snapshot,...and the VSES **DID** activate at part throttle accel just a short time ago. at around the same speed but, I was doing a SLIGHT turn.


SUPER!!! It seems its the steering harness, I just haven't had time to spend on the car letely....i'll keep you all posted. Thank you for your help. If anyone has had a similar problem, and KNOWS the fix,...let me know.

Thanks

 

Again fella's, thank you for your input in the past on this subject.

I think we figured it out.....1 YAW sensor later(as advised by GM TACH) and one steering sensor later.

The exhaust, which is a 3" setup, runs VERY close to the DIFF and transmission on the passenger side of the vehicle. In most cases, it's pressed against the trans. It's near impossible to take move it away anymore. We've tried, and tried. YOu can only move it soo much, without making the tips uneven. Were gonna try some exhaust wrap to push it away, or provide some cushion.

Soo...just a heads up.

J