4WD light after driving

[TrisGT]

Recently got my C34 S2 on the road. Loving it and it drives great despite all its issues. However I’m having constant trouble with the ATTESA system. The 4wd light is off on cold start, and the car drives great. After a while of driving after the cars warmed up, the 4wd light turns on. It’ll turn off if the car sits for halfa or so. 
when the light comes on, there’a a weird vibration under hard acceleration. I do have a wheel bearing that’s on it’s way out but I can’t see how that would cause an issue such as this. 

[GTSBoy]

Do diagnostic. Investigate returned code.

[RBW49N]

The wheel bearing may be that bad it doesn’t read the wheel speed sensor properly?

[niZmO_Man]

Don't guess, get the ATTESA code read, or search here on how to get codes from it

[czeno]

Have you checked attessa fluid level inside the r/h panel at rear? With engine running too.

[SLIXK]

I thought the 4WD turns on itself when it detects slip. Mine is also off on start up but turns on and off at certain times.

Edited October 5, 2021 by SLIXK

[BiggestRon22]

mines just always on, even once it warms up. it had a moment where it would turn off but its gone back to staying on all the time.

abs light does the same too.

[Ben C34]

On 11/10/2021 at 5:33 PM, BiggestRon22 said:

mines just always on, even once it warms up. it had a moment where it would turn off but its gone back to staying on all the time.

abs light does the same too.

Your car is f**ked then. That's not normal mate.

[BiggestRon22]

On 11/10/2021 at 1:06 AM, Ben C34 said:

Your car is f**ked then. That's not normal mate.

Any suggestions for what to do with it?

[Ben C34]

Find out what is not happy. Get someone with a proper diagnostic device connect to the car and see what it says.

[Butters]

The atessa unit under the rear parcel shelf has a light on it. A series of blinks gives you a number that is a fault code.  On this forum is the code numbers and the fault. 

 

It can range from really easy to solve to very damn hard.  

Mine fell in the hard category, multiple codes and after fixing some I just replaced the setup with a full race unit and never looked back