Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Useless

As the owner of a 1981 and a 1984 Mercedes 300SD, I find this manual absolutely useless. I have recently attempted to find information about the operation of power windows, the engine cooling system and the air conditioning system only to be frustrated by the total lack of any information about these systems in my children's vehicles. I'm currently looking for an manual for these vehicles more along the line of the user friendly, informative Hayne's manuals I had been used to.