Custom certificate authentication for WCF service

Question

i am using a WCF service which is using "Transport" binding for communication and Certificate for authentication.

My service is hosted in IIS. i have to override the default authentication of WCF/IIS and write custom implementation.

i implemented Custom X509 validator but Api call does not even reaches the validator and fails before that.

is there a way to override the default authentication behavior?

Configuration:--

<service name="MyService" behaviorConfiguration="MyServiceBehavior">
        <endpoint binding="basicHttpBinding" bindingConfiguration="testBinding" 
           contract="MyService"/>
</service>

<basicHttpBinding>
     <binding name="testBinding"
         maxReceivedMessageSize="2147483647">
      <security mode="Transport">
         <transport clientCredentialType="Certificate"/> 
     </security>    
    </binding>
</basicHttpBinding>

<serviceBehaviors>
    <behavior name="MyServiceBehavior">
      <serviceMetadata httpsGetEnabled="true" />
       <serviceDebug includeExceptionDetailInFaults="true" />
        <serviceCredentials>
         <clientCertificate>
          <authentication certificateValidationMode="Custom"          
             customCertificateValidatorType="TestCertificateValidation 
              ,MyService"/>
         </clientCertificate>
       </serviceCredentials>         
     </behavior> 
   </serviceBehaviors>

Custom Validator:--

public class TestCertificateValidation : X509CertificateValidator
{
   public override void Validate(X509Certificate2 certificate)
   {                
     return;
   }
}

Thanks in Advance.