German AI Voice Agents for Automotive: Service Calls, Not Advertising

German AI voice agents for automotive book workshop appointments and remind owners about service in German, and follow a customer who switches to English. In Germany, an advertising call to a consumer needs prior express consent under UWG §7, documented and kept five years, and from 2 August 2026 callers must be told they are speaking with an AI.

Key Takeaways

• Adding an offer turns a service call into Werbung under UWG §7.
• Keep every advertising consent record for five years, and log each use.
• Name the AI assistant and the recording in the first sentence.

This post is part of our guide to AI voice agents for automotive and dealerships. The guide's section on German-speaking customers notes that a German dealership runs the same calls under different consent law. This post covers that law and the German call itself for an Autohaus using Dograh, an open-source, self-hostable voice agent platform. It is general information, not legal advice.

A service call and an advertising call fall on opposite sides of UWG §7

In Germany, whether a dealership may make an AI call depends on whether the call advertises. The unfair competition law, the Gesetz gegen den unlauteren Wettbewerb (UWG), sets the rule in §7 Abs. 2. Nr. 1 treats as an unreasonable nuisance any "Werbung mit einem Telefonanruf gegenüber einem Verbraucher ohne dessen vorherige ausdrückliche Einwilligung", meaning a phone advertising call to a consumer without prior express consent.

A call that confirms a booked Werkstatttermin, or returns a callback the customer asked for, is generally a service call and not Werbung. Add one sentence about a winter-tyre offer or an accessory package, and the same call generally becomes advertising. So the agent's service calls carry no offers at all, and any offer goes on a separate call to customers whose consent is on file. Reminder calls follow the same split, covered for every market in AI Voice Agents for Service Reminders in Automotive.

Nr. 2 adds a second rule: advertising "unter Verwendung einer automatischen Anrufmaschine" needs the prior express consent of the person called, with no exception for business contacts. Whether an AI voice agent counts as an automatische Anrufmaschine has not been settled by the courts. A dealership calling fleet managers could rely on presumed consent under Nr. 1 if the agent is not such a machine, and could not if it is. The cautious reading is to treat express consent as the rule for every AI advertising call, consumer or fleet, until counsel tells you otherwise.

Consent records have to last five years

UWG §7a turns consent into a record-keeping job, and the regulator is enforcing it. Under §7a, a business that advertises by phone to a consumer must document the consent "zum Zeitpunkt der Erteilung in angemessener Form", at the time it is given, and keep that proof for five years from when it was given "sowie nach jeder Verwendung", and after each use. Under §20, a call without consent can draw a fine of up to €300,000, and missing records up to €50,000.

The Bundesnetzagentur, the federal regulator for unwanted calls, reported 39,842 written complaints about unlawful phone advertising in 2025, up from 37,561 in 2024. It handled 13 large fine proceedings, with fines of more than €1 million in total, and for the first time it fined companies for failing to document and keep advertising consent.

For a voice agent, that means the consent record lives in your own system, usually the dealer management system (DMS) or a customer relationship management (CRM) system, and only customers with a record go on an advertising list. Each call is a use, so the webhook that runs after the call writes the date and the call's ID back to the consent record. Dograh Campaigns retry a busy or unanswered line up to the limit you set, with no cap per person, so your list also decides how often anyone is called.

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The first sentence names the AI and the recording

The Greeting Text is fixed text that Dograh speaks word for word, so it is where the disclosures belong. Article 50(1) of the EU AI Act requires AI systems that talk directly with people to be designed so that "the natural persons concerned are informed that they are interacting with an AI system", unless that is obvious. Article 50(5) says this must happen "at the latest at the time of the first interaction". It applies from 2 August 2026.

Recording needs the same care. Under §201 StGB, whoever "unbefugt das nichtöffentlich gesprochene Wort eines anderen auf einen Tonträger aufnimmt", recording someone's private words without authority, faces a fine or up to three years in prison. Dograh records calls, and there is no per-agent switch. Self-hosted, recording can be turned off only for the whole server. So either the greeting says the call is recorded, in words your counsel approves, or recording is off.

A line that serves German and English callers needs both languages, because the Greeting Text plays the moment the call connects, before any language is detected: "Guten Tag, hier ist der KI-Assistent des Autohauses Becker. Dieses Gespräch wird aufgezeichnet. Hello, you can also speak English with me."

Then the agent uses the formal "Sie" throughout. Before it names a car or a booking, it verifies: "Nennen Sie mir bitte die letzten vier Zeichen Ihrer Fahrgestellnummer oder Ihre Postleitzahl." The Fahrgestellnummer is the vehicle identification number (VIN). Read-backs follow German habits: dates in words, "Dienstag, der dritte November", and the Kennzeichen letter by letter, so a misheard plate is caught before the booking is written.

German and English on one call

One agent can serve both languages, as long as it never guesses which one it heard. In the agent's Model tab, set the speech-to-text Language dropdown to Multilingual (Auto-detect), then tick German and English under Language Hints. The hints apply only to languages the Flux multilingual model supports, and Deepgram's language list includes German for Flux multilingual.

When the agent is not sure, it asks: "Möchten Sie lieber auf Deutsch oder auf Englisch weitersprechen?" It switches only after the customer answers. If a call cannot continue reliably in either language, the agent hands it to German-speaking staff through Transfer Call, which works on Twilio only, or records a callback request in the customer's language.

The voice has to speak German too. ElevenLabs lists German for its Eleven v3, Multilingual v2 and Flash v2.5 models, and Cartesia lists German for Sonic 3.6. Add service words such as HU/AU (the roadworthiness and emissions inspection), Inspektion and Reifenwechsel, plus your model names, to the agent's Dictionary, which works with Deepgram and Dograh speech-to-text.

Keep the agent to standard dialogues, such as the Werkstatttermin in the spring and autumn tyre-change rush or an HU/AU reminder. SkillSprinters, a German training provider, wrote in May 2026 that German voice systems work reliably "für klar abgegrenzte Standarddialoge", for clearly defined standard dialogues, and that is a sensible limit to design for. The wider pattern for a second language is in Spanish AI Voice Agents for Logistics and Delivery: What Changes in Spanish.

Where the call data sits under the DSGVO

A workshop call carries a name, a Kennzeichen, a Fahrgestellnummer and often a home address, and under the DSGVO, the German name for the General Data Protection Regulation (GDPR), all of it is personal data. Dograh Cloud names no EU data region. You can place the call data in the EU by self-hosting Dograh in an EU data centre, and the audio stays there only when the speech and language models run there too.

If you use model providers through your own API keys, each one hears the audio. Each then needs an Auftragsverarbeitungsvertrag (AVV), the data processing agreement under Article 28 of the GDPR. Dograh has no retention setting, so your own policy decides how long recordings and transcripts are kept. Quality assurance (QA) summaries come out in English by default, so have a German-speaking reviewer read the transcripts of flagged calls. Why Voice Data Needs to Stay Local covers the privacy case in more depth.

Self-hosted Dograh has no per-minute platform fee, though servers, model keys and phone minutes still cost money. Dograh Cloud has a 1¢-a-minute platform fee. Start with inbound Werkstatttermin calls, which raise no advertising question, and confirm your consent and recording wording with a Rechtsanwalt before the first outbound call.