How to get money from a person who. have to pay us back

My father bought an auto ricksaw through a financer on emi on downpayment of 1.17 lakh with all things included like RC,INSURENCE,permit,etc no badge and license though but we soon handed back the auto to the dealer within 10days and asked him we don't need this auto so he cut down 6 months emi and other charges and issues us a cheque of 90k. Now the problem is he wrote the date 10 days in future but he is asking us not to put the cheque into the bank as he does not have sufficient balance and telling if we did he will file a false case against as he has the file in which my father signed for the auto and i don't know what are the things written on the file that my fatger signed upon and he was quite confident about it and no longer seems to pay back.What shall we really do like should we file case or we politely as him to pay back? we have just the cheque as proof and some witness who can speak for us in court..and tell me what is the false case that he case file and how to deal with that..thank you