You can verify the proper implementation of the Google Consent – Advanced or Basic Mode with the help of Google Tag Assistant. 

1. Login to Google Tag Assistant.
2. Add your website domain.
3. Click on the Connect.
4. Refer to the left event section of the screen.

Refer to the below scenarios to validate if your GCM is working properly.

• For Advanced Consent Mode via Manual Script implementation, 
  Consent Default must be fired as the first command before any other command on page load.
  
  
  
  

• For Advanced Consent Mode via Google Community Template implementation,
  Consent Default must be fired after the Consent Initialization Command on page load.
  
  

• For Advanced Consent Mode,
  Consent Default for all the consent types must be in line with the default settings made by you in Mandatly Community Template/Manual Script.
  
  
  
  

• For Basic Consent Mode via Google Community Template or Manual Script implementation, 
  Default Consent must not be fired on page load.
  
  

• For Advanced Consent Mode via Google Community Template or Manual Script implementation,
  Update Command must be fired as per the consent given on the cookie banner.