Can a htv license holder, drive cars ?

I'm in need to get answer for this question

Please do mention the Law that supports this thing.

Recently a friend of mine met an accident and he was driving a Maruti Dezire Car.  He holds HTV (Heavyweight Traffic Vehicle) .The insurance people had said that they cannot process the claim as the person holds HTV license and was not authorized to drive the vehicle.

Please reply as early as possible, is there any law that can prove that HTV license holders can drive Motor Cars (Maruti Dezire) for personal use.

Thanks.