Active Handling Warm-up message on '03

[Blade]

About once a month after starting my Vette, I will receive the above message in my DIC for about 15 seconds followed by a "warm-up complete" message. This even happens in the heat of the summer and after only been turned off for 5 minutes while I run into the store.

Can't tell or feel any problems with the car.

Any ideas?

 

[PJay]

NC 50anny,

I believe that's normal for your C5, and not a cause for concern. The same thing happens on my '01, as well as a friends '03.

 

[Skull One]

Guess you missed the last thread on it from about 6 days ago. But here it is again on the whys.

There is a g-force sensor (accelerometer) package behind the ashtray.
The sensor package is made of solid state components. IE: Plastic, Ceramic and Silicon.
This sensor measures the yaw rate, wheel speed/spin, accelerator position and steering input to determine if the back end is comming around faster than it should be.

For a solid state g-force sensor to work properly it must come up to a certain tempature that is within so much of the overall package (IE mounting and other components) tempature around it. Since plastic/ceramic/silicon cools faster than the rest of the overall package, it can takes a few mins to stabilize the temp of the sensor to the package. When everything is at the same temp to begin with, IE in the morning, then the system can calibrate and do proper g-force detection right off the bat. Tunnel heat is the single biggest issue for making the overall package temp differ from the one very sensitive component (accelerometer) inside the package.

Hope that helps clear part of this up. And yes, this is a VERY basic explanation and I did cut a few corners. But I don't think you want the long drawn out explanation

 

[Blade]

Guess you missed the last thread on it from about 6 days ago. But here it is again on the whys.

There is a g-force sensor (accelerometer) package behind the ashtray.
The sensor package is made of solid state components. IE: Plastic, Ceramic and Silicon.
This sensor measures the yaw rate, wheel speed/spin, accelerator position and steering input to determine if the back end is comming around faster than it should be.

For a solid state g-force sensor to work properly it must come up to a certain tempature that is within so much of the overall package (IE mounting and other components) tempature around it. Since plastic/ceramic/silicon cools faster than the rest of the overall package, it can takes a few mins to stabilize the temp of the sensor to the package. When everything is at the same temp to begin with, IE in the morning, then the system can calibrate and do proper g-force detection right off the bat. Tunnel heat is the single biggest issue for making the overall package temp differ from the one very sensitive component (accelerometer) inside the package.

Hope that helps clear part of this up. And yes, this is a VERY basic explanation and I did cut a few corners. But I don't think you want the long drawn out explanation

Thanks for that detailed information, I understand you.

I got this response from a fellow 2003 owner that likely fits into your answer:

At the "50th Celebration" event in Nashville, Dave Hill was asked about this at one of the seminars. He said it usually means the car's computer is trying to determine what "straight ahead" is, and needs to travel in a straight line for a few yards before it can assist you (thus the warning)...

 

[Tuna]

I got this response from a fellow 2003 owner that likely fits into your answer:

[OUOTE]At the "50th Celebration" event in Nashville, Dave Hill was asked about this at one of the seminars. He said it usually means the car's computer is trying to determine what "straight ahead" is, and needs to travel in a straight line for a few yards before it can assist you (thus the warning)... [/OUOTE]

Maybe this explains why I got the message one day while playing in a parade. I had stopped and restarted the car several times while positioning the car and it was 85 degrees outside. After one restart, I started to move the car and zigzagged it several times only to get the 'warming up' message. It must have needed to know which way was straight.

 

[Skull One]

Thanks for that detailed information, I understand you.

I got this response from a fellow 2003 owner that likely fits into your answer:

At the "50th Celebration" event in Nashville, Dave Hill was asked about this at one of the seminars. He said it usually means the car's computer is trying to determine what "straight ahead" is, and needs to travel in a straight line for a few yards before it can assist you (thus the warning)...

I actually should have mentioned that in my explanation. But I figured most people drive their car within 30 seconds of starting them up and the accelerometer would already be looking for straight while comming up to temp.

 

[Tuna]

I actually should have mentioned that in my explanation. But I figured most people drive their car within 30 seconds of starting them up and the accelerometer would already be looking for straight while comming up to temp.

Probably true for most but not always so when you're playing in a parade or some similar situation.

 

[erenneckar]

Warm up complete

Me too, i get the light every once in a while. I can be just driving thru town...taking it easy and on comes the light... WARMING UP then WARM UP COMPLETE. Does anyone have the answer why this system does this for no real apparent reason. I posted this thread a few months ago and i was told by several vette owners that this was normal but somehow it doesn't seem normal. I would like a vette mechanic aka C4C5 specialist to respond to this thread. Thanks, and keep up the

 

[Timster]

I have gotten that message a few times on my 2003 Z06. And it's usually at the strangest times. But I haven't been in any situations where it caused a problem.
I was a little concerned when I first noticed it though.
Tim

 

[erenneckar]

This is really wierd because like you said this light comes on at times when the machine is not being stressed or needed. Can someone in the know comment on this, Thanks

 

[modman]

My belief is that residual heat is somehow transferred to the sensing unit while the vehicle is stopped. After restarting the vehicle and getting some air moving, (start rolling down the road), the heat from underneath the car diminishes, and the effect on the accelerometer is eliminated. (msg goes away)

 

[Blade]

Guess we can assume....


The road to Corvette Heaven is a Straight and Narrow Path!


:eyerole

 

[DRTH VTR]

"warming up"

I suspect that a better message would be "active handling calibrating", rather than "warming up". I suspect it has nothing to do with heat or cold; only with where the steering wheel is when it is pointed straight ahead.

 

[Skull One]

Re: "warming up"

I suspect that a better message would be "active handling calibrating", rather than "warming up". I suspect it has nothing to do with heat or cold; only with where the steering wheel is when it is pointed straight ahead.

Go read up on accelerometers, they have to stablize tempature first BEFORE they can look for straight properly. If you want to be 100% sure (IE seeing is believing), take a can of cold spray and spray the circuit board down to about freezing after the tunnel has come up to temp. Just don't crack the ICs in the process.

 

[Blade]

Guess we can assume....


The road to Corvette Heaven is a Straight and Narrow Path!


:eyerole

And since the accelerometers have to warm-up first, we can also assume....

"....You have to go through He77 to get to heaven!"

 

[TexasRedZ06]

The Active Handling System warmup on the C5 has nothing to do with ambient temperature or having any of the AH circuits heat up. Its a calibration for the system just as Dave Hill explained. The system needs to know what straight is. I have had this message many times and it can be easily duplicated. I've experimented with different things that cause the message, and here is what I've found:

1) Before you shut off the car, turn the steering wheel more than 180 degrees from center and leave it there. I've found that the car needs to be sitting for about 3 minutes before restarting.

2) When you drive off, drive at least 25 yards and don't go past 9 mph.


You will get the "warmup" message.

I have driven the car in both 40-100 degree weather and the message can be duplicated. I can also skip any of the above, and the message will never show. For example, you start the car and quickly hit 10 mph, you'll never see the message.

The reason I don't believe the temp stabilization of the AH components matters, is that I can duplicate this after the car has sat all day. If the car sits for 8 hours, all the temps will be equal with the sensors, so the warm-up calibration technically would not be necessary. However, I can get the car to display the warmup message by steps 1 and 2 if the car sits for 3 minutes or for 48 hours in any weather conditions.