Debugging
How to debug Consent Mode v2 in Tag Assistant
Find a missing default, late update or unexpected tag with a repeatable Tag Assistant and browser DevTools workflow.
In brief
Debug the event timeline first, then confirm browser requests and storage match the intended mode.
Start from a clean visitor
Open GTM Preview or Tag Assistant in a new profile with no stored consent. Connect to the exact published URL and avoid accepting the banner before the debugger attaches. Select the earliest event in the left-hand timeline and open the Consent tab.
Inspect the default
Confirm the four signals have a default, usually denied for a new visitor. If the default is missing, inspect the page head or GTM Consent Initialization trigger. If it arrives after tags, fix execution order before investigating reports.
Tag Assistant can show a signal state even when a third-party tag ignores it. Check firing rules for non-Google vendors separately.
If the default arrives late, revisit the GTM initialization sequence before changing individual event tags.
Inspect the update
Make one banner choice without a reload. Select the event after the interaction and compare consent values. Try analytics-only and reject-all choices; a blanket grant is a mapping defect. Then withdraw and check the next event.
Compare with real browser activity
In DevTools, clear Network, preserve log and reload. Filter Google endpoints and inspect Cookies/Application storage. Basic mode should hold Google tags and their requests before permission; Advanced mode can send cookieless pings with denied consent. Unexpected optional cookies or full hits need investigation.
- Write down the page URL, container version, consent state and exact request.
- Repeat after a hard refresh and on a second page to catch persistence errors.
Record a pass or fail
A useful handoff contains screenshots of the default and update events, a request trace, the chosen mode and the expected mapping. If GA4's Consent settings screen remains unchanged immediately after a fix, allow for its processing delay and rely on Tag Assistant for the immediate implementation check.
Try it
Find the next check for your symptom
Look at the earliest event, then inspect your head snippet or GTM Consent Initialization trigger. The default must run before Google tags.
Continue with a related guide
Primary sources
- Google: Troubleshoot consent mode(opens in a new tab)
- Google Analytics: Verify consent settings(opens in a new tab)
Reviewed 15 October 2026. Validate product interfaces and requirements for your own implementation.
Check the implementation on your site
Consentory helps teams inspect trackers, configure prior blocking and document consent choices. The guides above give you a test plan before rollout.