Expert System for diagnosing Automobile problems

the Expert system approach is in such a way that it has two session, the specifics n general(in the interface) the specifics shows the user the common problems abt cars n their causes n how to deal wit it(that is for the mechanic to follow n the user to know) and den, the general gives the user an opportunity to type in the symptoms he/she noticed b4 the car broke down n den, wen he supplies the answer, the expert system den starts asking the user some related ?s n den finally tells the user the problem to the car pataining to the ans given by the user, the specifics is categorized into two sections, the electrical problem n the mechanical problem ie, electrical n mechanical problems of cars n den ?s will be given on each aspect already drafted the ?s for the expert system to ask but I don't know hw to go abt it cos dats were the JESS comes in. n den i want to grade each ans in the sense that if the ans the user gave were majorly yes n its like 70% then the expert system gives it the solution built on it but if its like 70% of No!, den it has its own ans......as in for each ans the user gives like Yes / No it will be graded n if the ans are majorly Yes den the expert system will tell the user ok, the battery for ur car is weak n if the user should ask y the system will be like 'cos its nt supposed to make such noise while u r driving or so, n den it gives the solution like ' u nid to change the battery" n matter ends but if its a situation whereby the ans the user gave is majorly No! den the system will den ask the user to select the nxt option in the problem category n ans the ?'s from there, the user will be able to know wots wrong wit the car. I have designed the interface using Netbeans 6.9.1 already.. PLEASE, i will need the coding to be done in Jess but as a last result, if u can do it in java please notify...but JESS is the priority here. Thanks...