What Consent Mode V2 controls
The CMP captures the choice; Consent Mode communicates it. analytics_storage and ad_storage govern storage, ad_user_data covers sending user data for advertising, and ad_personalization covers personalized advertising. These signals replace neither the banner nor checks for other destinations such as Meta or LinkedIn.
Basic and Advanced compared
| Question | Basic | Advanced |
|---|---|---|
| Before consent | Google tags blocked; no data to Google | Google tags load with defaults; restricted measurements possible |
| On rejection | No data to Google | Cookieless measurements; no storage prohibited by denied signals |
| Ads conversion modeling | General model | Advertiser-specific model, subject to eligibility |
Basic does not eliminate all conversion modeling. Advanced does not guarantee a fixed number of recovered conversions. Google describes the distinction in its Consent Mode documentation.
Cookieless does not automatically mean anonymous or legally permitted. Document the chosen mode and assess the actual data flows.
Five errors to test directly
- Late default. Check whether dependent tags run first. CMP templates and manual integrations have different initialization paths.
- Missing update. Test acceptance, rejection and partial choices separately.
- Competing defaults. A manual snippet must not overwrite the CMP decision.
- Incorrect mapping. Analytics consent must not accidentally enable advertising use.
- Unchecked destination. A correct Google signal does not establish how third-party tags or server templates behave.
The Usercentrics guide follows the chain into the server. The GA4 audit guide covers other measurement failures.
Debug with Tag Assistant instead of a fixed gcd format
Open Tag Assistant and inspect the earliest consent state and the update following the banner choice. Then compare network activity and server preview against expectations for the selected mode.
gcs and gcd carry consent information. Google notes that encoding may change. An eight-character pattern is not a reliable decoder, and the presence of gcd alone does not establish that Consent Mode is active.
QA before the next release
Test first visit, stored choice, acceptance, rejection, partial consent and withdrawal. Repeat relevant cases after SPA navigation. Record expected cookies, requests and states per destination in the CMP/GTM QA template.
The June 2026 change concerns controls in linked GA4/Google Ads setups. Keep it separate from the choice between Basic and Advanced.