When an insurance contract has been taken out to cover the pecuniary consequences of civil liability arising from the use of the vehicle which caused the accident and if the insurer invokes an exception to refuse its cover or reduce its scope, the guarantee fund must meet the obligation to reimburse provided for in article R. 421-64.
In the case provided for in the previous paragraph, the insurer must declare the exception invoked to the guarantee fund within a maximum period of six months from the date on which he became aware of the facts giving rise to the exception. The guarantee fund may, within a period of six months from the date of this declaration, contest the merits of the exception invoked.
If the guarantee fund exercises its right to contest, the insurer shall reimburse it the sums for which the guarantee fund is liable pursuant to the first paragraph of this article. If the insurer fails to make such reimbursement, it may be forced to do so by an order of the juge des référés made at the request of the guarantee fund.