The complete guide to the GA4 + ASC Events connector

1. What this is
2. Requirements
3. Install (once, ~5 min)
4. Connect a data source
5. The fields
6. Rules of the road
7. Forward compatibility & audits
8. Multi-store setups
9. Troubleshooting
10. Registering ASC parameters
11. Subscription licensing
12. Updating & maintenance

A Looker Studio community connector that pulls data from Google Analytics 4 with an automotive layer on top. This guide covers the current release — Connector v1.3.0, built on ASC spec v1.2 (47 events: 41 standard + 6 optional).

1. What this is

• Every GA4 field on your property — all standard dimensions and metrics (traffic sources, devices, geography, pages, sessions, users, ecommerce…) plus any custom dimensions/metrics registered on the property. The field list is built live from your property, so new fields appear automatically.
• The ASC layer — all 47 ASC (Automotive Standards Council) v1.2 events, classified and ready to use: friendly event names, lead channels (Phone / Chat-SMS / Form / Video), conversion classes, department classifications, quality tiers, 18 lead buckets, 15 calculated rate metrics, and 23 pre-declared vehicle parameters.
• Multi-property rollups — combine multiple GA4 properties into a single data source with automatic Property ID and Property tagging.
• Traffic filtering — built-in checkboxes to exclude internal traffic and test/staging hostnames.
• Forward-compatible event architecture — dynamic registry overrides via Script Properties, unclassified-event alerts, and built-in audit tools.

2. Requirements

• A Google account with at least Viewer access to the GA4 property (only the person creating the data source needs this — report viewers don’t, see §8).
• The website must send ASC events (asc_click_to_call, asc_form_submission…) to that GA4 property for the ASC lead fields to have data. All regular GA4 fields work regardless.
• The two connector files: Code.js and appsscript.json.

3. Install (once, ~5 minutes)

3.1 Create the script

1. Go to script.google.com (signed in with your GA4-access account) → + New project. Name it GA4 ASC Events.
2. Project Settings (gear) → check Show appsscript.json manifest file in editor.
3. Editor: in Code.gs delete the contents and paste in all of Code.js; in appsscript.json delete the contents and paste in all of appsscript.json.
4. Save (Ctrl+S).

3.2 Enable the Analytics APIs — do not skip

Pasting the manifest lists the services but does not switch the APIs on. In the left sidebar:

1. Under Services, if AnalyticsData or AnalyticsAdmin already appear, remove both and Save.
2. Click Services (+) → add Google Analytics Data API.
3. Click Services (+) again → add Google Analytics Admin API.
4. Wait 1–2 minutes for enablement to propagate.

Verify: in the toolbar function dropdown pick test_listProperties → Run (authorize when prompted) → open the execution log. You should see your GA4 properties. A 403 … has not been used in project means the APIs aren’t enabled yet — redo this section and wait another minute.

3.3 Create the deployments (two — they serve different people)

• For yourself (testing): Deploy → Test deployments → copy the Head deployment ID. It always runs the latest saved code, but only works for accounts with access to the script — never share it.
• For everyone else (production): Deploy → New deployment → gear → select Looker Studio Connector → description “v1” → Deploy → copy this Deployment ID. This is the ID you share; it works for any Google account. Two mistakes both produce The linked connectorId was invalid for other users: sharing the head ID, or not link-sharing the script project as Viewer.

Shipping updates: Deploy → Manage deployments → edit → Version: New version → Deploy. The ID never changes, so existing users are unaffected until you choose to ship.

3.4 Share the script — required for anyone else to connect

Unlisted connectors require every user to have read access to the Apps Script project. In the editor click Share → General access: Anyone with the link → Viewer → Done. The script won’t appear in users’ Drives, and your Script Properties (Stripe keys etc.) are never visible. If “Anyone with the link” is unavailable, your Workspace admin has external link-sharing disabled.

4. Connect a data source

1. Open (replacing your ID): https://lookerstudio.google.com/datasources/create?connectorId=YOUR_DEPLOYMENT_ID
2. Authorize both prompts. On the “Google hasn’t verified this app” screen — normal for a personal script — click Advanced → Go to GA4 ASC Events. It’s your own code, read-only.
3. Configure: GA4 Property (dropdown of every property your account can read), Additional GA4 Property IDs (comma-separated, to roll up multiple stores), ASC events only (leave OFF for general use — see §6.2), Exclude internal traffic, Exclude test / staging hostnames, and Allow GA4 Property to be modified in reports for multi-store setups.
4. Connect → review the field list → Create report.

5. The fields

The field picker is grouped: ASC fields sit in their own labeled ASC ► sections, separate from GA4’s own categories. Hover any field for a description.

5.1 Connector & multi-property metadata

Connector Version (e.g. 1.3.0) · ASC Spec Version (v1.2) · Property ID · Property (display name) — the last two power multi-store rollups.

5.2 ASC ► Classification (10 dimensions)

5.3 ASC ► Leads & Engagement (18 bucket metrics)

No double counting: channel lead metrics count parent submission events only; department metrics count the derivative events, which are mutually exclusive per submission.

5.4 ASC ► Rates (15 calculated metrics)

Calculated in Looker Studio with AUTO aggregation (division by zero safely yields null):

1. Form Completion Rate = Form Leads ÷ Form Engagements
2. Chat Conversion Rate = Chat Leads ÷ Chat Engagements
3. Phone Connect Rate = Voice Calls ≥ 30s ÷ Click-to-Calls
4. Phone Lead Rate = Phone Leads ÷ Click-to-Calls
5. Phone Connect-to-Lead Rate = Phone Leads ÷ Voice Calls ≥ 30s
6. Video Completion Rate = Video Leads ÷ Video Engagements
7. Overall Lead Rate = Total Leads ÷ (all engagements)
8. Overall Appt Rate = (Sales Appt + Service Appt) ÷ Total Leads
9. Appt Rate (Phone / Chat-SMS / Form / Video)
10. Appt Rate (Sales) and Appt Rate (Service)
11. Unclassified Lead Rate = Unclassified Leads ÷ Total Leads

5.5 GA4 · Vehicle (23 pre-declared dimensions)

These populate automatically from custom event parameters once registered in GA4 Admin → Custom definitions (see §10).

Core vehicle: Item Make, Model, Year, Trim, Price, VIN, Stock Number, Condition, Body Style, Color, Fuel Type, Location, Category, Payment, Inventory Date, Search Result Count.
EV-specific (optional, new in v1.2): Battery Life %, Odometer, Range (miles), Charge L1 (hrs), Charge L2 (hrs), Charge L3 (hrs), Drivetrain.

6. Rules of the road

6.1 Don’t mix session/user metrics with lead metrics in the same chart

A chart mixing Sessions (or Total Users) with Phone Leads forces a hidden per-event breakdown; the session numbers become “sessions containing that event” and re-add wrongly. Same page is fine, same chart is not.

6.2 The “ASC events only” checkbox

OFF (default): all events flow; property-wide metrics (Sessions, Users, Pageviews) are correct, and ASC fields still work. ON: every query is filtered to the 47 asc_* events — perfect for dedicated lead data sources, wrong for Sessions/Users.

6.3 Traffic filters

Check Exclude internal traffic for production reports (filters hits flagged in GA4 Admin). Check Exclude test / staging hostnames to strip out localhost, staging., dev., qa., test.

7. Forward compatibility & audits

7.1 Dynamic event overrides (ASC_EVENTS_OVERRIDE)

If a vendor introduces new ASC events, add them without redeploying. In Apps Script → Project Settings → Script Properties, add ASC_EVENTS_OVERRIDE as a JSON string, e.g. { "asc_voice_sms_submission": ["Voice SMS Lead", "Phone", "C"] }.

7.2 test_auditEvents()

Run test_auditEvents() in the editor to audit all events received by a property in the last 30 days. The log lists known ASC events, unclassified ASC events (start with asc_ but missing from the registry), and top non-ASC events.

7.3 test_listKnownLimitations()

Run test_listKnownLimitations() for a real-time summary of supported features vs GA4/Looker Studio platform boundaries.

8. Multi-store setups

1. Rollup data source (built-in): enter multiple property IDs into Additional GA4 Property IDs; use the Property or Property ID dimension to break down or filter by store.
2. One data source per store: duplicate the data source, switch the property, duplicate the report page.
3. Property override: tick Allow GA4 Property ID to be modified in reports; editors switch the property per report copy.

9. Troubleshooting

10. Registering ASC parameters

GA4 only exposes event parameters and user properties to reporting after registration under Custom definitions:

1. In GA4: Admin → Data display → Custom definitions → Create custom dimension (or metric).
2. Name it (e.g. Item Make), scope Event (or User), Event parameter = the exact ASC parameter name.
3. Repeat, then Edit data source → Refresh fields in Looker Studio. New fields appear labeled “(custom)”.

Registration is not retroactive — GA4 collects parameter data from the day of registration forward.

10.1 Key mapped parameters (closed-list)

10.2 Dynamic parameters (free-text)

event_owner (vendor sending the event, required on all events), submission_id, item_make / item_model, item_id (VIN), item_price, item_year, item_number (stock #), and — new in v1.2 — page_layout, page_template_style, process_name, plus element_text / element_title.

10.3 Optional EV parameters (new in v1.2)

10.4 User properties (user-scoped)

user_id, secondary_id, secondary_id_provider (e.g. vistadash, carnow, marchex — 78 standard vendor slugs), user_type, oem_brand, store_name, oem_code.

11. Subscription licensing (optional, Stripe)

Configured entirely via Apps Script → Project Settings → Script Properties:

The data-source creator’s Google email must belong to a Stripe customer with an active or trialing subscription. Report viewers are never checked. Verdicts are cached (6 hours for subscribers, 10 minutes for unlicensed accounts), and a per-email circuit breaker fails open during Stripe outages so paying users are never locked out. Run test_checkLicense() for the full diagnostic.

12. Updating & maintenance

• Connector updates: paste the new Code.js (and manifest if changed) → Save. The head deployment picks it up instantly for testing; ship it to users via Deploy → Manage deployments → edit → Version: New version → Deploy (the production ID never changes).
• Schema: self-refreshes within ~5 min; force with Refresh fields.
• Nothing else to maintain — no keys to rotate, no servers. Access follows GA4 permissions: lose property access and the data source stops.

Questions about the connector? See the connector FAQ or contact VCTRS via vctrs.io.