Timothy Barth

After owning this C6 for 12 years I traded it today after being scared to death last week.Driving along about 35 miles an hour the brakes suddenly locked up,sending the car almost sideways. I was lucky no one was passing me or on my right side. The service acting handling message also came on. If this could be definately fixed I would get it fixed and keep it. I took the car to a Chevy dealer and was told it would be a $450.00 repair and the mechanic also told me it was not a quarenteed fix. I believe he said it was a faulty steering position senser. I do not know how anyone can continue to drive a car knowing at any moment this could happen. I have also read the other depressing threads on here about this problem. I loved this car but this is too much of a serious problem to live with.

jrose7004

$450.00 for a repair these days is not too bad. I had a steering sensor replaced on both a C5 Corvette I had as well as a Tahoe. The only symptom that I had was that the cruise control wouldn't stay engaged.

Timothy Barth

You are right about the price,but the fact that they are really guessing at what caused this is what got me. The brakes locking up on their own is quite frightning.

Ahrmike

on the freeway before this occurred, did you hit a speed bump or were you making a slight turn?

Also, do you normally use the telescoping steering wheel?

Had this happen to me, was able to fix it for under $100....

02_NHRA_TA

OP, sorry to hear about your issue. Glad you're ok. I'll get the message every once in a while but luckily no brake lock, fingers crossed. I have notice that the message seems to show up more when I use the a/c or when I have my other car's fob in my other pocket (could just be a coincidence). Just curious, what did you trade it in for?

​​​1k3y, what did you to to fix yours?

Timothy Barth

No bumps, I was in a slight curve to the left, and I hardly ever use the telescoping steering wheel. This just seem to happen for no reason that I could see. I did not get it fixed. I got rid of it. I will miss it for sure, but will not miss the headaches that came with it, although I have to admit it was a very good car most of the years I had it.

Timothy Barth

I traded for a 2017 Honda Civic SI. These days a Honda is about all I can afford.

ruxvette

Seriously? Even though the dealer said a steering position sensor was the likely culprit you passed on the fix and sold the car.
But you told the Honda dealer/buyer of the problem, right?

Ahrmike

As these C6s with telescoping columns age i suspect we will see many more of these failures. These can and WILL cause accidents on the highway.

The root cause of the problem is the steering angle sensor which falls out of its mount when you use a telescoping column that is failing. The steering column worm gears which allow it to move up/down corrodes over time of inactivity/age and locks the center shaft of the column. When you have the column as far towards you as possible (tall people), and you dont move it for a while, it will be far more likely to fail.

When the center shaft locks up, the column will still move up and down and end up locking up against the steering angle sensor at the base of the steering column. The SAS is (stupidly, i might add) mounted via shitty GM plastic mounts. The column motor wins against the mounts, punches it through the mounts and the SPS will end up "free hanging".

The AHS system uses the SAS to dtermine which way the steering wheel is pointed and if you hit a bump, the SAS "jumps" so the car thinks you're trying to turn, but using the YAW sensor it realizes the car ISNT turning. This makes it lock up tires in an attempt to get you out of a slide that isnt actually happening.

When I first had these symptoms i was driving my car into a 90degree city street turn and the brakes started randomly locking up. I figured it was just bad roads/big tires so I ignored it - then, i got on the highway and went into a slight turn and hit a bump - the bump knocked the SAS and my car started slamming brakes left and right. Luckily, i didn't spin out and i was able to disconnect the SAS and drive with my "AHS error" lit up.

To fix it, its relatively easy:

First, you have to disconnect the steering column. MUCH easier than you would think. Just make sure you dsiconnect the battery (air bags), and you tape the steering wheel to the cowl behind it (to prevent cable reel failure).

The column itself only mounts one way to the shaft coming through the firewall. Bottom two kick panels and the top steering wheel bezel have to be removed, and then its just a few electrical connectors and 4 big bolts. Make sure the SAS doesnt spin by itself either - it is zeroed from factory and it is a pain in the *** ot get it zeroed again. The telescoping motor is also kind of a pain to remove, you need 12 pt sockets... of 5 or 6mm IIRC.


Once removed, you have to put rust penetrant/grease back into the worm gears to unjam and free the column. Once its freely moving, the column is fixed.


Two things causing this:

1) Shitty GM plastic mounts (really, such an important part and you couldnt use a goddamn aluminum mount??)

2) rust/binding of telescoping wheel


Its also possible that your TPMS, yaw sensor, or BCM is going bad but i have seen a few other posts regarding this SAS mount issue and I believe it'll show up a lot more in humid states/taller drivers/low mileage C6s.



Are you sure you didnt "bump" the column forward or backwards? or that you dont have "easy entry" or whatever its called turned on? The EE automatically moves the steering column up/down to get you into the car easier...


My symptoms did show up during a slight curve on the highway as well.


I guess you were just over the car tho, sometimes you get over a vehicle and its time to move on. Looks like this was the straw that broke the camels back?

Sad to hear of a fixable car being traded to a dealer though, If I was local I would've checked it out for you and tried to fix it so you could get some more $ from it at the very least.

cottonant

Am I correct in assuming "Active Handling" is turned off when "Traction Control" is disabled?

owc6

This is a horrible and well- known issue, which for some affects the car at high speeds. Some others , this is only a slow speed issue. GM has ignored this issue (among others ) and has done nothing to address this during the entire C6 generation.

If you want an in depth tutorial, and eye-opener, there is a sticky at the top of the C6 Tech forum.

Bruze

I've seen similar stories on here before about brakes locking up.

Wonderful: Nannies that could kill you. How did we ever survive before The Age of Nannies for Everything?

I hate to think of what would happen if someone was going 150-ish and this happened.

EDIT: I see you mentioned the high speed occurrence, Mrs. Ow. You posted while I was reading the thread.

Ahrmike

If you want to fully disable the AH all the time you can disconnect the steering angle sensor. It'll throw the AHS code and if you have the 08+, you wont get launch control... but it will basically turn off everything. HOWEVER I suggest leaving it on. Ive been testing the AHS on and off when I have a large flat space... the AHS works extremely well when its working. I suspect that you'd be far more likely to encounter bad road conditions where AHS will save you than the AHS hurting you via (random) failure. As far as this telescoping handle BS...

Still, GM better watch out for lawsuits. The SAS failing is scary as **** when it activates on the highway. Pretty sure I have flat spots on my front tire from when it locked them up.

irok

if traction control button only pressed once active handling is still operational.

Cheeser

This just happened to me this morning. I was leaving the store and got the "Service Active Handling / Service Traction Control" message. The car began misfiring when I put it in gear, then the brakes locked up stopping my car before I could do so myself. I called for a tow and now sit waiting to hear back as to the culprit and cost.

I could not imagine this happening if I was actually moving at highway speeds, it scared the sh*t outta me when going 5mph..

Ahrmike

wow, that sounds like a totally different issue.. Not sure why the car would misfire unless you thought it was a misfire due to the random on/off brake pulsation? when the brakes actuate the entire car does buck though.

Have you used the telescoping wheel recently? If you can peek under your dash, take a look along the steering shaft coming from the firewall. You should see some wires going into a sensor (SAS), if that sensor is hanging/free to rotate then you have the same problem that I had.

Cheeser

Thanks for the quick reply!! The "misfire" could have been my misinterpreting what was happening because it was definitely startling when it happened.
I had the car towed to the dealership and they called saying they would call me tomorrow with a diagnoses. So I am waiting to hear from them.
I have not changed the telescoping setting since I purchased it new back in 2011. It is set at the maximum length setting. I will mention it if they don't tomorrow.

cottonant

Thanks iroc. I went to the trusty 2006 C6 owner manual and found this on page 4-11:

You can turn the system off if you ever need to. If you turn the Active Handling System off, the Traction Control System will also be turned off. Adjust your driving accordingly.

To turn the system off, press the ACTIVE HANDLING button on the console for five seconds. You can turn the system on at any time by pressing the button.
The DIC will display the appropriate message when you push the button.

As a newbie I would appreciate someone explaining why I should not turn this potentially dangerous system off every time I get in the C6.

Ahrmike

hey, no problem. No way your knee or fingers tapped that telescoping adjustment? If not, then its likely that it was something else setting it off.

I noticed that mine was set to full extended too, this seems to exacerbate the lockup issue. I have mine set to full + 1 quick "tap" down so that it won't lock up now...

Only other thing that can set off AHS TCS is the yaw sensor/speed sensor/TPMS sensor as far as i understand the system.

Ahrmike

I think the potential to be a problem is there - however, its possibly more likely to help than to hurt - assuming the SAS sensor mounts aren't as problematic as I fear. If they aren't, then i dont see it being any different than the ABS systems that we all rely on now. Yes, if it fails it will crash the car. However, chances are that the system will help you retain control of the car more than the chances that it will wreck your car.

Again, if you disconnect the SAS under the steering wheel, it will ALWAYS be off. It will throw an AHS code on your dash though.... and reconnecting it will NOT clear it. It has to be cleared by a tech 2. (I've read that it clears itself after a few hundred start-stops once the code is stored, but have not tested it myself).