We've got it in at the dealer service centre at the moment but they can't find the problem. It doesn't happen all the time but it's very bad when it does. At low battery when trying to accelerate the car jolts and shudders violently. I suspect the diesel engine is cutting in and out rapidly. It must be bad for the car as it shakes it around a huge amount. It only ever happens at low or empty battery and seems to be more likely when under load for example going up a hill.

Please if anyone has an idea where to look for an issue let me know so I can notify the service centre.

Glen.