Auditor refuses appointment at AGM

No consent is obtained before the appointment of the auditor. I think ur getting confused betweem auditor and director. Consent is required to be given by director of a public company before his appointment.

Provisions for the auditor are as follows:

u/s 224: Co gives the notice to auditor within 7 days of appointment (i.e. 7 days after passing the resolution) The Auditor then within 30 days of receipt of the notice from the co wrt the appointment intimates the ROC in form 23B of the approval or rejection of the appointment.

i hope this makes it clear, that the auditor may or may not accept the appointment after the resolution is passed.

As regards the certificate u/s 224(1B) i dont think( though it looks so, prima facie) that the giving of the certificate means the approval of the auditor wrt to the appointment. In my opinion..it may rarely happen, but the Sec 224 does preserve the right, even after the appointment by the co, for the auditor to decide on the appointment irrespective of the certificate furnished

Further the words of the Sec 224(1B) say "Appointment if made, shall be within the ceiling on number  of audits" 

Hence i feel this clarifies just the mere eligibility and not the final acceptance of the auditor