I am wondering what to expect traveling snowy mountain roads in a new to me 1999 sport wagon. Bentley's says you can not over-ride the throttle control portion of the ASC by turning the ASC off. I have new Blizzaks and 16 inch wheels for winter travel. Does anyone have any experience with this that they would like to share? The road to our local ski hill is primitive. Thanks in advance.
I don't have experience w/ your car, but I'd think as long as you have some traction and momentum, you'll probably mostly be able to keep the car pointed where you want. I don't think ASC however is completely capable of compensating for the lack of a limited slip differential - I would suspect that sometime there may be no substitute for getting power to both rear wheels. I also wonder, if you're in an extremely low-traction situation, if the ASC, between computer-controlled brake application/throttle modulation/power reduction, might completely kill your ability to keep the momentum going, and in effect get you stuck where you otherwise mightn't have.
ASC operation Not sure about the details of the Bently manual but they are frequently not accurate. On the E39 with ASC+T the ASC button allows you to toggle the system on or off. When it is off the warning triangle will be lit all the time. Otherwise it flashes when the system is taking action to avoid slippage. You can deactivate the throttle control by turning off the ASC. This allows wheel slippage that you then must control yourself with the accelerator. The owner's manual does say to turn off the ASC when you are stuck in heavy snow or ice. My esperience is that you should leave the ASC on all the time - EXCEPT when stuck or if you are in a condition where you are loosing traction and slowing down. An example of this would be going up a hill in very heavy snow. This will cause some wheel slippage and the system will start to reduce engine power, or apply the rear brake to prevent the slippage. This can acutally cause you to loose momentum and in those conditions it is better to turn it off and rely on your own ability to keep the car moving but under control. Turning off the system only affects the "traction control" function and does not affect the ABS braking function. And remember - the traction control is only that - to "control" the traction. In other words it helps prevent you applying too much torque for the available friction. It prevents wheel spin so as to prevent spin outs. Later versions (DSC) add more features and have varios stages of deactivation. I understand they also allow slightly more wheel slippage at slow speeds so as to improve the ability to move in those very heavy going situations (or if you are stuck on ice or in snow). Your best assist is always 4 good tires - and of course "full winter" tires for winter conditions. Cheers Jim Cash
From my understanding and research, there is also a half on/half off mode as well. You know if you push the ASC/DSC button once, the light illuminates to warn you that the system is disabled. Well, if you hold the ASC/DSC button down until the illuminated ASC/DSC light goes off again and you have half ASC/DSC mode, which will allow you to get your car out of a slippery situation. It has been discussed at BF.c many times and if you run a search (I'm feelin too lazy to find it for ya), you should be able to find the info to help you understand exactly what is going on in that mode. GL...
