Why is my XC so useless in the snow?

[ifnt420]

If gear selector function is reduced, could it cause confusion to the TCM giving too much torque off the line, hence the wheel spin?
Anyway, you definitely needs to have the codes read to make sure what exactly is wrong.

[cmercon]

I appreciate everyone's help, I think we may be onto something about too much off the line because this morning I just drove through the largest storm we have had this year. Once I got going everything went smooth, even up some nasty unplowed hills. I just fear if I had to stop for whatever reason on one of those hills I would not be able to start again. We'll see if I can make it up my driveway.

[cmercon]

How new are the snow tires on the vehicle? I know at least with summer tires it can take a couple hundred miles for them to wear in and perform their best, could this potentially be the case with your snows?

Only a couple hundred miles on them.

[JRL]

As much as I hate to say this, try winter mode (W)

[TrueBlue]

I found this video on YouTube. It would indicate that what is being experienced is consistent with the way the VC functions. It also illustrates the point wgriswold makes referencing post #9 in the other thread. So get the front wheels spinning enough in these situations and the rears should kick in eventually, I guess. Not an ideal system which is probably why it was redesigned for 2003.

The old VC does NOT engage until the vehicle is moving (exactly how much "moving", I don't know) I tied the car to a mature tree, made sure the grass in my field was wet then tried to drive away - gently then - not so. Front wheels span madly and the rears - zilch.
Attached the same tree and rope to an early XC90 - result was as you would expect.

Volvo UK kindly (?) gave me some money to "go away"

For some reason both paddles (or whatever) need to be spinning before the goo transmits any power.

[JRL]

With the V/C AWD the rear tires must turn at least 1- 7th of a rotation.
If the car isn't moving (ie: tied to a tree) it won't work.
Even early Haldex systems won't start until (I believe) 1-5th of a rotation. Not until 2006 and "instant traction was programed into the Haldex, will it then work immediately

[cmercon]

The old VC does NOT engage until the vehicle is moving (exactly how much "moving", I don't know) I tied the car to a mature tree, made sure the grass in my field was wet then tried to drive away - gently then - not so. Front wheels span madly and the rears - zilch.
Attached the same tree and rope to an early XC90 - result was as you would expect.

Volvo UK kindly (?) gave me some money to "go away"

For some reason both paddles (or whatever) need to be spinning before the goo transmits any power.

I guess that may be part of the answer.

[KB3MMX]

With the V/C AWD the rear tires must turn at least 1- 7th of a rotation.
If the car isn't moving (ie: tied to a tree) it won't work.
Even early Haldex systems won't start until (I believe) 1-5th of a rotation. Not until 2006 and "instant traction was programed into the Haldex, will it then work immediately

JRL, can "instant traction" be programmed into the 03-05 cars?



.

[JRL]

No

[wgriswold]

With the V/C AWD the rear tires must turn at least 1- 7th of a rotation.
If the car isn't moving (ie: tied to a tree) it won't work.
Even early Haldex systems won't start until (I believe) 1-5th of a rotation. Not until 2006 and "instant traction was programed into the Haldex, will it then work immediately

I think that explains what I saw. The car was backing out of a flat driveway and the rear tires were stuck in a small icy depression at the end of the driveway. The front tires were spinning on the snowy driveway but couldn't move the rear tires out of the depression so the rear tires were not rotating and thus no AWD. This was an 01 or 02. I have not experienced such behavior with my 03. If I had I wouldn't keep it.

I want AWD or 4x4 to get me going from a stop. Once I am going I don't have much use for it. When I had my 1980 DL I preferred it to my 4x4 truck once the vehicles were moving. The DL although only rear wheel drive tracked better and I felt more in control.