05 4.8iS . DSC/4x4 warning only when cold ???

[nrgetic99]

My 06 4.8iS with 55k has developed and odd fault. When it is cold out (below 40 degrees, relative, I know) , the DSC/4x4 warning lamp comes on and stays on at startup.

I do not get the dreaded 3 warning light DSC/Check engine/Battery issue.

It goes away when the vehicle gets warm.

It did stay on for about a day last week and went away when I put in a new battery as a maintenance item. Oddly enough, it came on for a minute with the new battery so I rechecked and attached the cables and it went away after 15 ft of driving. The old battery was only replaced as it is 4 years old but it checked out fine on a battery tester at the supplier of the new battery after I had already put the new one in.

This morning, 37 degrees at start up, on it comes. I drive to the stealer to make an appointment and when I get back in the car, its off again.

Anyone have any ideas / experience ?

I have read and re-read the manual and posts here...what potential damage may I be doing driving with it on ? I do have an appointment to be reamed with a smile by the dealer in the morning.

Thanks

David

[JCL]

Could be related to the fluid in the transfer case, since the fault is temperature dependent. When the fluid goes out of spec you get a warning.

What you really need is for the codes to be read so that you aren't just guessing. Go to the dealer, and don't think of it as reaming, think of it as education. Decide once you know what the codes are how you would like to fix it.

[RMak]

I had this problem before. When it was cold, I used to get the DSC Warning Lamp, Brake light at times. Ended up that my Alternator was going south. Since it's been replaced, all has been good.

Also you're best bet is to get the codes read too.

Good luck!

[nrgetic99]

Originally Posted by JCL

Could be related to the fluid in the transfer case, since the fault is temperature dependent. When the fluid goes out of spec you get a warning.

What you really need is for the codes to be read so that you aren't just guessing. Go to the dealer, and don't think of it as reaming, think of it as education. Decide once you know what the codes are how you would like to fix it.

Good advice as always !

I was leaning toward a fluid issue although I was not aware of the degree of sophistication of fluid monitoring in the xfer case.

I should know in the morning.

I assume codes should be stored even if they are not current at time of inspection ?

David

[nrgetic99]

Seems I have a weak alternator. I am mad for not checking that myself first. Anyway, as its 'water cooled' and BMW, we are talking $650 plus labor. Nice.

It males sense as battery has been tested and is fine. I am getting low voltage warnings and various idiot lights so charging system must be the culprit. I am relieved its not truly an Xdrive or DSC issue.

With the Air suspension ECU and this in the last 4 weeks, I am starting to get a bad feeling.

Oh yeah, and the stealer told me they will not install a non BMW part so time to dig deep.

Don't get me wrong, its hands down the nicest to drive most competent vehicle I have ever owned and I love driving it comes at a price ....

David