Have you ever heard from car owners or mechanics the phrase “installed a new GU into the car” and wondered what that means? Abbreviation in automotive slang GU stands for head unit - the central element of the multimedia system, which is responsible for audio, navigation and communications. Without it, a modern car loses half of its functionality: no music, no maps, no hands-free phone.

But the GU is not just a “radio tape recorder”, as many people think. Modern head units have evolved into full-fledged computers on wheels, integrated with on-board electronics. They control rear view cameras, connect to the Internet, support Apple CarPlay and Android Auto, and some even know how to diagnose car problems. In this article we will figure out what are types of GI, how they work and what to look for when choosing - so as not to overpay for unnecessary functions and not be left without communication on the road.

What is a PG in a car: a simple explanation

Head unit (GU) is the central unit of the car’s multimedia system, which combines:

  • 🎵 Audio system (radio, USB, Bluetooth, streaming)
  • 🗺️ Navigation (built-in maps or connection to a smartphone)
  • 📞 Telephony (calls via speakerphone, SMS reading)
  • 📹 Connecting cameras (rear view, all-round view)
  • 🔧 Diagnostics (in advanced models - reading errors OBD-II)

In fact, this is the “brain” of the entire infotainment system (from the English. infotainment — infotainment system). Even if your car has a separate screen for climate control or a digital instrument panel, GI remains the main node, which manages media and communications.

Example: when you connect iPhone by CarPlay, it is the head unit that processes the signal, displays the interface on the screen and transmits the sound to the speakers. Without the GU, all these functions would not be available - you would have to use a separate navigator and a suction cup column.

📊 What head unit is in your car?
Standard (standard)
Aftermarket (purchased)
No GU (radio only)
I don't know

Types of head units: from cassette tape recorders to Android computers

GIs evolved along with cars. Just 20 years ago these were simple cassette players with radios, but today they are full-fledged multimedia centers. Let's look at the main types:

GI type Features Pros Cons
1-din (1DIN) Classic size (height 50 mm). Suitable for most cars. 🔹 Cheap
🔹Easy to install		 ❌ Small screen (or no screen at all)
❌ Limited functionality
2-din (2DIN) Double height (100 mm). Most often with a touch screen. 🔹 Large display
🔹 Video and navigation support		 ❌ More expensive than 1DIN
❌ Not every car will fit
Standard (OEM) Factory installed. Often integrated with the on-board system. 🔹 Fits optimally into the salon
🔹 Supports auto functions (climate, heating)		 ❌ Expensive update
❌ Closed firmware
Android car radios Work for Android, support application installation. 🔹 Flexibility (you can install any software)
🔹Support Google Maps, Yandex.Navigator		 ❌ Slows down over time
❌ Requires updates
Apple CarPlay / Android Auto Smartphone interface on the GU screen. Requires USB/Bluetooth connection. 🔹 Familiar phone interface
🔹 Regular updates		 ❌ Only works when your phone is connected
❌ Limited functionality without a smartphone

Important: not all GIs are interchangeable. For example, in Toyota Camry 2020 regular GU integrated with the system Safety Sense, and replacement with an after-market version may disable some of the security features. Please check compatibility before purchasing!

What is the difference between 1DIN and 2DIN?

1DIN - standard size (180x50 mm), suitable for most cars. 2DIN is twice as high (180×100 mm), allows you to install a screen with a diagonal of up to 7 inches. However, not all machines support 2DIN - for example, in VAZ 2110 or Renault Logan the first generation there is no place for it without redoing the panel.

Functions of modern head units: what can your GU do?

A modern GU is not just a music player. Here are the main features to consider when choosing:

  • 🎶 Audio formats: support MP3, FLAC, WAV, streaming (Spotify, Apple Music).
  • 📡 Radio: FM/AM, DAB+ (digital radio), RDS (display song titles).
  • 📱 Smartphone integration: Apple CarPlay, Android Auto, MirrorLink.
  • 🗺️ Navigation: built-in maps (Garmin, Navitel) or online services (Google Maps, Yandex.Maps).
  • 📹 Video: Playback from USB/SD, support DVD/Blu-ray (rarely), output to additional screens.
  • 🔌 Connections: Bluetooth, Wi-Fi, USB-C, HDMI, AUX.
  • 🚗 Auto integration: climate control, reading data from CAN buses, diagnostics OBD-II.
  • 🔊 Sound: equalizer, support DSP (digital audio processing), amplifier outputs.

Critical feature: if your GI supports CAN bus, it can control vehicle functions (for example, automatically mute the music when talking on the phone or show data from the on-board computer). However, this requires the correct firmware and adapters.

💡

Before purchasing, check whether the GU supports codec aptX for Bluetooth. It provides high-quality lossless sound - important if you listen to high-resolution music.

How to choose a head unit: 7 key parameters

The choice of GI depends on your needs and budget. Here's what to look for:

  1. Vehicle Compatibility: Check the size (1DIN/2DIN) and the presence of adapter frames. For example, for Volkswagen Golf You may need an adapter to connect to the standard wiring.
  2. Operating system:
    • 🤖 Android - flexibility, but lags are possible.
    • 🍎 Apple CarPlay/Android Auto - stability, but dependence on the phone.
    • 🖥️ Own OS (for example, Pioneer or Alpine) - optimized, but limited in applications.
  3. Screen: diagonal (from 6.2 to 10 inches), resolution (800×480 or better 1280×720), touch or button.
  4. Connections:
    • 🔌 USB (better USB-C)
    • 📶 Bluetooth 5.0+ (for stable connection)
    • 🌐 Wi-Fi (for online maps and updates)
    • 🎧 AUX (if you need an analog input)
  • Navigation: built-in (does not require Internet) or online (more precisely, but requires a SIM card or connection to a phone).
  • Sound: number of pre-outs (minimum 4 for acoustics), support DSP, amplifier power (from 50 W per channel).
  • Additional features:
    • 📹 Camera support (rear, 360°)
    • 🔧 Diagnostics OBD-II
    • 🔐 Anti-theft features (such as removable panel)

    Check the size (1DIN/2DIN) and compatibility with your car|

    Make sure the audio formats you want are supported (FLAC, WAV)|

    Rate the screen quality (resolution, brightness)|

    Check availability Bluetooth and USB-C|

    Check to see if adapters are needed to connect to the standard wiring -->

    Budget options (up to 15,000 ₽): Pioneer MVH-S320BT, JVC KD-X361BT - simple models with Bluetooth and USB, no screen.

    Middle segment (15 000–40 000 ₽): Sony XAV-AX5500, Alpine Halo9 iLX-F411 - touch screens, Apple CarPlay, good sound.

    Premium (from 40,000 ₽): Pioneer AVH-Z9200DAB, Kenwood Excelon DMX906S - high resolution, DAB+, support 360° cameras.

    Installing a PG: can you do it yourself?

    Install the head unit yourself maybe, but there are nuances. If you have a standard 1DIN-GU (for example, in Lada Vesta or Kia Rio), the process will take 1–2 hours. For 2DIN or standard systems (for example, in BMW or Mercedes) you may need:

    • 🔧 Transition frame (for panel mounting)
    • 🔌 Wiring adapter (for example, ISO connector)
    • 📡 Antenna adapter (if you change the standard GU)
    • 🔊 Amplifier (if you want to improve the sound)

    Step by step instructions for 1DIN:

    1. Disconnect the battery (remove the negative terminal).
    2. Remove the decorative panel around the old GU (usually it is held on by latches).
    3. Disconnect the power and speaker connectors (remember or take a photo of the order!).
    4. Install the new PG into the slide (metal frame) and connect the wires.
    5. Check the work before final assembly.
    What should I do if the sound does not work after installation?

    1. Check if the speakers are connected correctly (plus to plus, minus to minus).

    2. Make sure that the correct sound source is selected in the GU settings (USB, Bluetooth).

    3. If you are using an amplifier, check the signal level at the RCA outputs.

    4. In some cars (for example, Ford) you need to activate the audio system through the diagnostic scanner (Forscan).

    ⚠️ Attention: In vehicles with the system Start-Stop (for example, Audi, BMW) When the battery is disconnected, the on-board computer settings may be reset. Write down or take a photo of the current settings (for example, cruise control, lighting)!

    If you are not confident in your abilities, it is better to contact an auto electrician. Connection errors can lead to:

    • ⚡ Short circuit (if you mix up the power supply).
    • 🔇 Loss of sound (incorrect speaker connection).
    • 🚨 The alarm is triggered (if you touch the CAN bus).

    Top 5 mistakes when choosing and installing GI

    Even experienced car owners sometimes make mistakes. Here are the most common mistakes:

    1. Buying a 2DIN in a car where it won’t fit. For example, in Hyundai Solaris of the first generation, only 1DIN is standardly installed. To install 2DIN, you will have to cut the panel or buy an adapter.
    2. Ignoring speaker impedance. If the power supply is designed for 4 ohms, and the car has 2 ohm speakers, the sound will be distorted and the amplifier may burn out.
    3. Saving on wiring. Cheap Chinese adapters may melt or cause interference. It is better to take branded ones, for example, from Connects2 or Scosche.
    4. Untested compatibility with CarPlay/Android Auto. Some GIs (especially cheap ones) Android-models) support these functions only on paper, but in reality they are buggy.
    5. No backup power. If the GU has a touch screen, the settings may be reset after disconnecting the battery. The solution is to install a capacitor or backup source.
    ⚠️ Attention: In cars Toyota and Lexus with the system Entune Replacing the standard control unit may disable the function eco mode and adaptive cruise control. Consult your dealer before replacement!

    An important nuance: if your GI supports OBD-II, but does not show fuel consumption or error data, please check if it is compatible with your vehicle's protocol (eg CAN, K-Line). Some Chinese devices only work with a limited set of brands.

    The future of head units: what awaits us?

    Technologies do not stand still, and GIs are evolving towards complete integration with the car and the outside world. Here are the trends to expect in the coming years:

    • 🤖 Artificial Intelligence: voice assistants (Alice, Google Assistant) will not only carry out commands, but also predict your needs (for example, suggest a route to work at the usual time).
    • 🚘 Autonomous driving: GI will become part of systems ADAS (driver assistance), displaying data from cameras and radars in real time.
    • 🌍 5G and cloud services: Streaming video to 4K, online games, video conferencing directly from the salon.
    • 🔋 Wireless charging and connectivity: no wires for CarPlay/Android Auto, charging gadgets through the GU screen.
    • 🔒 Cybersecurity: protection against hacker attacks (now Tesla regularly releases patches for its multimedia systems).

    Interesting fact: in Mercedes-Benz new generation (for example, EQS) State University operates on the basis Linux and has an open architecture that allows you to install third-party applications - almost like on a smartphone. Perhaps this trend will soon spread to mass brands.

    However, progress also has a downside: the smarter the GI becomes, the more difficult it is to repair it. Already many owners BMW or Audi are faced with the fact that after updating the firmware, certain functions stop working (for example, control gestures or voice input).

    💡

    When choosing a GI, look not only at the current functions, but also at the possibility of updates. Manufacturers like Pioneer or Alpine support their devices longer than no-name brands.

    FAQ: Frequently asked questions about head units

    Is it possible to install an Android car radio in any car?

    Theoretically, yes, but there are limitations:

    • 🔹 Must be the right size (1DIN or 2DIN).
    • 🔹 Adapters are needed to connect to the standard wiring (especially if the car has CAN bus).
    • 🔹 In some cars (for example, Mazda with the system MZD Connect) replacing the PG disables some functions (climate control, heated seats).

    To accurately check compatibility, use services like Crutchfield (enter your car model).

    Why does the audio steering control not work after installing a new control unit?

    This is a common problem. Reasons:

    • 🔹 There is no adapter for connecting the buttons on the steering wheel to the new GU (you need CAN adapter or SWI interface).
    • 🔹 Wires are connected incorrectly KEY1/KEY2 (there should be a diagram in the instructions for the GU).
    • 🔹 Steering wheel control mode is not activated in the GU settings.

    Solution: Buy an adapter (eg. Pac RP4 for Toyota) and connect it according to the diagram.

    Which GU is better: with or without a screen?

    Depends on your tasks:

    GU with screen GU without screen
    🔹 Convenient for navigation and video 🔹 Cheaper
    🔹Support CarPlay/Android Auto with display output 🔹Easier to install
    🔹You can connect cameras 🔹Less distractions from the road
    ❌ More expensive ❌ No visual navigation
    ❌ May overheat in the sun ❌ Limited functionality

    If you only need music and your hands are free, 1DIN without a screen is enough. If navigation and multimedia are important, take a 2DIN with a display.

    How to update the firmware on the GU?

    The process depends on the model, but the general scheme is:

    1. Download the firmware from the manufacturer's official website (for example, Pioneer or Kenwood).
    2. Copy the file to USB flash drive (usually to the root, without folders).
    3. Insert the USB flash drive into the GU and go to the update menu (most often Settings → System → Software Update).
    4. Confirm the installation and wait for it to complete (do not turn off the power!).
    ⚠️ Attention: Do not use firmware files from torrents or unknown sources! This may “brick” the device. For example, in Sony XAV-AX1000 After an unofficial update, the sensor stops working.
    Is it possible to connect a rear view camera to the GU?

    Yes, if:

    • 🔹 The GU has a video input (RCA or AV-IN).
    • 🔹 The camera is connector compatible (usually RCA or Mini-Jack).
    • 🔹 In the GU settings there is a mode Rear view camera (sometimes activation via menu is required).

    To automatically switch to the camera when reverse gear is engaged, an additional wire is needed that connects to the reverse lamp.