I am currently rebuilding a car as a hobby. As a part of it I am planning on building in a car PC with custom software for some multimedia usage, navigation and some diagnose usage. I know there are pre-built systems to buy and install in the car but thats not what my question is.

For the PC itself I am planning on using a Raspberry Pi(2) with either Debian or Arch Linux. I will create the software for the audio player, navigation and diagnose by myself.

Some time ago a friend of mine told me that a car PC isn't "allowed" to have a visible boot or loading screen. He said that the system has to be available as soon as the car is started.

  1. Is this true?
  2. Are there any requirements for car PCs and the software running on it? And if so, where can I find these requirements?

I already tried searching for it but couldn't find anything. I am from Germany so i'm primarily interested in answers fitting the german law but i'm open for any information about this topic.

Note: This is my first question on SE so please tell me if I did something wrong so I can improve my question.

  • Well, kind of depends on what you consider to be a booting screen. I know the multimedia systems of some cars have a splash screen which usually shows some logos. Clearly the system boots during that. If you're making that for yourself then I wouldn't see a problem with the Pi showing the verbose boot screen as well, I doubt you'd lose your MOT over that. Apr 19, 2016 at 13:00
  • Interesting question. In the US, the only "requirement" that I know of is that the screen that the driver sees can't play video except for a reverse camera or similar. But I'm not sure if that law applies to aftermarket modifications or not.
    – JPhi1618
    Apr 19, 2016 at 13:00
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    @EChan42 not at the moment. But as i am a great fan of opensource i will make the whole source-code public. At the moment there is not much to make public because i work on the concept. The MPD sounds like a good idea. But i will develop the software by myself with Lazarus. For the sound i either use BASS library or UOS
    – Requion
    Apr 19, 2016 at 15:29
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    @r3qui0n1s please keep me posted on this! This is what I've been planning for ages. Have you considered using BT or either USB to communicate between the Pi and the cars OBD port? You could for example make music louder once the car is moving at hight speeds and lower when it comes to a stop.
    – EChan42
    Apr 19, 2016 at 15:44
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    @EChan42 i can do this. Atm i plan on implementing diagnostics for things like oil temp and pressure, battery voltage, lambda values and maybe some more. My specific car lacks OBD or OBD2 support but i considered this also. With a log function to check the results afterwards.
    – Requion
    Apr 19, 2016 at 16:04

4 Answers 4


There is legislation known as "E-Mark" that pertains to electronic devices that are permanently installed in a vehicle. This car PC manufacturer is UK based and has a great description of the requirement.


Prior to March 2009 the regulations were extremely clear - all equipment installed into a vehicle on a permanent basis was required to be E-mark certified, and it was illegal to drive a vehicle that was fitted with non-compliant equipment. The regulations were changed in March 2009 and now require only devices related to safety-relevant functionality to be E-mark certified. Importantly, devices that have the potential to distract the driver are included in the safety-relevant category. Vehicle computers, which are capable of producing both audible and visual signals, clearly fall under this category and therefore still require E-mark certification.

However, as I also stated in my comments, I think that many of these rules and regulations are meant for manufacturers and businesses. If you want to make one computer and install it in your car, I'm not sure if any of this applies. You probably need to worry about anything that a police officer would see as an obvious distraction or safety issue like playing movies for the driver or hiding your view of the road or instruments on the dash, but I don't what other technicalities apply to an individual.


I was curious so I emailed the company quoted above to see what they had to say about someone building a one-off car computer. They didn't seem to have a definitive answer but this is what they said:

Thanks for your email. It's my understanding that if a person drives a vehicle with non-approved equipment fitted then they are potentially committing an offense.

However, I can't comment on how likely you are to run into trouble if it's your own personal vehicle and the equipment was fitted by you.

  • 2
    Thanks for this. I needed a moment to get this but now i know what you mean. The E-Mark is in general for car parts. Here in germany it is so that if there is an E-Mark you can use the part without further problems or modifications. If there isn't one you need to go to the TÜV to let a guy check the part specifically. This is called "Einzelabnahme" (engl. single acceptance)
    – Requion
    Apr 19, 2016 at 16:02
  • Thank you for the effort to email the company. I think there is not much of a message in the answer from the company :/.
    – Requion
    Apr 21, 2016 at 6:17
  • Yea, I wish they had more to say, but there's no real incentive to help a non-customer especially with what amounts to legal advice. Oh well, it was worth a shot!.
    – JPhi1618
    Apr 21, 2016 at 12:49

My 2012 Volkswagen Golf has an RCD510 multimedia unit which features a touch screen, card slot, USB connector, bluetooth and six disc drive, integrated front and rear parking sensors. I know that upgrades to this unit are available which include the ability to add integrated video for a rearward facing camera plus there is a version in inbuilt NAV.

This is most likely a close approximation of what you intend to build.

I can personally assure you that it doesn't power up instantly but takes a few seconds to boot up. During this time a "Welcome to Volkswagen" splash screen is displayed which is presumably covering some kind of console.

Within the UK, the only requirement I can think of is that they do not distract the driver. To this end, any units which play films will not show them on a screen visible to the driver whilst the handbrake is not engaged. Also, in the UK it is an offence to operate any handheld, wirelessly connected device such as a mobile telephone whilst driving. To this end, I guess you need to mount your unit physically on the dashboard and in a way that does not obscure the drivers view of the road or access to other controls.

Presumably local legislation is slightly different but I would have thought it will be loosely based on the same principles.

  • 2
    +1 for "not show them on a screen visible to the driver whilst the handbrake is not engaged". I will add this to my list. The only thing i can imagine which 'can' distract me would be the diagnostic feature. But this is similar to the additional instruments that can be used inside a car, therefore this shouldn't be a problem. I will build it into the controls in the center where you can find the radio for example. So it will be a physically built-in part of the car.
    – Requion
    Apr 19, 2016 at 14:23

This article speaks to how Android Auto complies with regulations:

Google built Android Auto so that it complies with recognized automobile safety standards, including the National Highway Traffic Safety Administration's (NHTSA).

So, it seems like they've already figured out what needs to be done to conform with existing NHTSA rules. The full Android auto website is at:


Additionally, they have an SDK available for download:



Check out http://www.mp3car.com/. The site has been around since c. 1999, and the forums include comprehensive discussion threads, on a variety of topics, among international "carputer" enthusiasts. A quick search for "germany law" yielded this result among others:

I got pulled several times in Germany and the Netherlands because the cops or customs officers wanted to have a look at the car and there was never any problem with the screen, although a movie was playing once or twice. My cars have also been passing the regular technical checks in the Czech republic and the Netherlands for 5 years without any issues related to the computers.

In CZ, there is no law, that would explicitly prohibit watching movies whilst driving. It falls under and could be prosecuted on basis of the general "the driver must fully focus on driving" rule. I think the situation is similar in the Netherlands, but I am not 100% sure.


For photos of installs, which may reveal some display options:


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    Welcome to the site! We welcome you knowledge and your input. While this post does have some useful information it seems to just be a plug for another site. That's why you have gathered the 2 downvotes to this post already. Apr 19, 2016 at 22:44
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    @Movemorecommentslinktotop Thank you for the clarification. If I were able to comment after just signing up for the site, I would have added the information as a comment to the OP's question. The site's rules forced me to use an answer to contribute the information. Apr 20, 2016 at 12:25

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