1. If FIR u/s 498A of IPC has already been registered by police based on your wife's complaint, you are required to apply for and avail AB immediately.
2. Section 498A of IPC is non compoundable, hence can not be withdrawn.
3. Ask her to submit an affidavit before the police affirming that she had lodged the complaint out of rage and that the differences have been settled mutually by and between you two and also that she does not have any grievance and complaint against you now.
4. After that file a petition before the High court for quashing the FIR based on the said affidavit of your wife and during the hearing of the quash petition, she should depose in your favour if questioned by the Court.
5.Pay her the settled amount at Court on the final day of hearing (being the day of the 2nd motion) of the MCD petition and also after the FIR could be quashed by you.