1. Introduction
This user manual provides detailed instructions for the installation, operation, and maintenance of your Mantian 7-inch Touchscreen Double Din Car Stereo. This multimedia system features Apple CarPlay, Android Auto, Bluetooth connectivity, FM radio, and supports a backup camera for enhanced driving convenience and safety.

Figure 1.1: Mantian Double Din Car Stereo with Apple CarPlay interface.
2. Safety Information
Please read all instructions carefully before installation and operation. Failure to follow these guidelines may result in injury, damage to the unit, or damage to your vehicle.
- Ensure the vehicle's ignition is off and the negative battery terminal is disconnected before beginning installation to prevent electrical shorts.
- Consult a professional for installation if you are unsure about any steps.
- Do not operate the unit in a way that distracts you from driving. Always prioritize road safety.
- Avoid exposing the unit to extreme temperatures, direct sunlight for prolonged periods, or excessive moisture.
- Use only specified voltage and power sources.
3. Package Contents
Verify that all components are present in the package before proceeding with installation.
- Mantian Double Din Car Stereo Unit
- Power Cord (Harness with naked wires)
- Horn Cable (Speaker Cable)
- Remote Control
- Steering Wheel Control (SWC) Unit
- Microphone
- Rear View Camera with 6M video cable and 1.5M power cable
- User Manual (this document)

Figure 3.1: Included components of the Mantian Car Stereo system.
4. Installation Guide
The Mantian Double Din Car Stereo is designed to fit standard double din openings. Its dimensions are approximately 178mm (L) x 104mm (H) x 46mm (D). Some vehicles may require an additional dash kit or modification for a perfect fit.
4.1 Wiring Connections
The unit comes with a harness with naked wires. Refer to the wiring diagram below for proper connections. It is recommended to test connections before fully securing the unit.

Figure 4.1: Rear connections and dimensions of the car stereo.
Key Connections:
- Left Audio Output: Connect to the left channel input of your amplifier or external audio device.
- Right Audio Output: Connect to the right channel input of your amplifier or external audio device.
- Video Output: For connecting to an external display.
- Subwoofer Output: For connecting an external subwoofer.
- Video Input: For connecting external video sources.
- Rear Camera Input: Connect the video cable from the backup camera here. The unit automatically displays the reverse image when reversing.
- ISO Power Cable: Main power connection for the unit.
- Microphone Interface: Connect the included external microphone for hands-free calling and voice commands.
- Radio Antenna: Connect your vehicle's FM antenna.
4.2 Backup Camera Installation
The included backup camera is designed for safe parking. Connect the 6-meter video cable from the camera to the "Rear Camera Input" on the stereo. Connect the 1.5-meter power cable of the camera to your vehicle's reverse light power source so it activates automatically when shifting into reverse.

Figure 4.2: Backup camera display on the car stereo.
5. Operating Instructions
The Mantian car stereo features a user-friendly digital control interface with a 7-inch HD touchscreen (1024*600 resolution).
5.1 General Operation
- Power On/Off: Press the power button (usually M/N or a rotary knob) to turn the unit on or off.
- Volume Control: Use the rotary knob or touchscreen controls to adjust volume.
- Menu Navigation: Swipe left/right or tap icons on the touchscreen to navigate between functions like Radio, Bluetooth, Phone Link, Card (SD card), AV In, F-CAM (Front Camera), Setup, and EQ.
- 7-Color Back-lights: The unit supports adjustable 7-color back-lights for the physical buttons. This setting can typically be found in the 'Setup' menu.

Figure 5.1: Overview of key features: FM Radio, Bluetooth, 7-inch screen, and Steering Wheel Control.
5.2 Apple CarPlay
CarPlay provides a smarter, safer way to use your iPhone in the car. Connect your iPhone to the unit via a USB cable. CarPlay allows access to phone navigation, contacts, messages, notifications, music, and more. Siri voice assistant can be used for hands-free control.

Figure 5.2: Apple CarPlay interface on the car stereo.
Voice Control with Siri
With CarPlay, you can use Siri to make calls, send messages, get directions, and control music using voice commands, enhancing driving safety.

Figure 5.3: Examples of intelligent voice commands.
5.3 Android Auto
Android Auto offers a safe way to use your Android phone while driving. Download the Android Auto app on your phone and connect it to the car stereo via a USB data cable. This enables access to navigation, calls, messages, and music from your Android device.

Figure 5.4: Android Auto connection and interface.
5.4 Bluetooth Connectivity
Pair your smartphone via Bluetooth for hands-free calls and wireless music streaming. Access your phonebook and call logs directly from the stereo's interface.
- Go to the 'BT' (Bluetooth) menu on the stereo.
- Enable Bluetooth on your phone and search for available devices.
- Select "CAR-BT" (or similar name displayed on the stereo) from your phone's Bluetooth list to pair.
- Once connected, you can make/receive calls and play music wirelessly.
5.5 FM Radio
Tune into your favorite FM radio stations. The unit allows for storing multiple stations for quick access.
- Select the 'Radio' icon from the main menu.
- Use the arrow buttons to manually tune or the 'AS' (Auto Scan) function to automatically search and save stations.
- Tap on the numbered presets (1-6) to quickly switch between saved stations.
5.6 Media Playback (USB/TF Card/AUX-in)
The stereo supports various media inputs for playing audio and 1080P video playback.
- USB: Insert a USB drive into the front USB port.
- TF Card: Insert a TF (microSD) card into the designated slot.
- AUX-in: Connect external audio devices using a 3.5mm audio jack to the AUX-in port.
5.7 Steering Wheel Control (SWC)
The unit supports steering wheel control. You can program your vehicle's steering wheel buttons to control various functions of the stereo, such as volume, track skipping, and mode switching. Refer to the 'Steering Wheel' section in the 'Setup' menu to configure this feature.
5.8 Equalizer (EQ) Settings
Adjust the audio output to your preference using the built-in equalizer. You can select from preset modes or customize the frequency bands manually.
Video 5.1: Demonstration of the Mantian Double Din Car Stereo's user interface, including radio tuning, Bluetooth pairing, phone link, equalizer adjustments, steering wheel control setup, and general system settings. This video provides a visual guide to navigating the stereo's features and customizing settings.
6. Maintenance
Proper maintenance ensures the longevity and optimal performance of your car stereo.
- Cleaning the Screen: Use a soft, lint-free cloth to gently wipe the touchscreen. For stubborn smudges, slightly dampen the cloth with water or a screen-safe cleaner. Avoid abrasive materials or harsh chemicals.
- General Cleaning: Keep the unit free from dust and debris. Use a soft brush or compressed air to clean vents and button areas.
- Temperature: Avoid leaving the unit in direct sunlight or extreme cold for extended periods, as this can affect performance and lifespan.
- Firmware Updates: Check the manufacturer's website periodically for any available firmware updates that may improve performance or add features.
7. Troubleshooting
If you encounter issues with your Mantian car stereo, refer to the following common troubleshooting steps.
| Problem | Possible Cause | Solution |
|---|---|---|
| Unit does not power on. | Incorrect wiring; Blown fuse; Vehicle battery issue. | Check power and ground connections. Inspect the 10A fuse on the back of the unit. Verify vehicle battery voltage. |
| No sound from speakers. | Speaker wires disconnected; Volume too low; Mute function active; Incorrect audio settings. | Check speaker wire connections. Increase volume. Deactivate mute. Adjust EQ and audio output settings. |
| Bluetooth not connecting. | Bluetooth not enabled on phone/stereo; Incorrect pairing process; Device too far. | Ensure Bluetooth is on for both devices. Re-attempt pairing. Move phone closer to the stereo. |
| CarPlay/Android Auto not working. | Faulty USB cable; Phone not compatible; App not installed (Android Auto); USB port issue. | Use a high-quality, original USB cable. Ensure your phone OS is compatible. Install Android Auto app if applicable. Try a different USB port if available. |
| Backup camera not displaying. | Camera power issue; Video cable disconnected; Incorrect camera input selected. | Verify camera power connection to reverse light. Check video cable connection to stereo. Ensure the stereo is set to the correct camera input. |
| Poor FM radio reception. | Antenna not connected; Weak signal area; Damaged antenna. | Check antenna connection. Try tuning to stronger stations. Inspect antenna for damage. |
8. Specifications
| Feature | Detail |
|---|---|
| Model | RK-7157B |
| Product Dimensions (Unit) | 178mm (L) x 104mm (H) x 46mm (D) / 7 x 4.09 x 1.81 inches |
| Item Weight | 1.32 pounds |
| Screen Size | 7 Inch Touchscreen |
| Screen Resolution | 1024*600 HD |
| Video Playback | Supports 1080P video playback |
| Video Encoding Formats | MKV / RMVB / AVI / MP4 / MDV |
| Connectivity Technology | Bluetooth, USB |
| Controller Type | Android, iOS |
| Compatible Devices | Android/iOS smartphones |
| Audio Output Mode | Stereo |
| Audio Encoding | Stereo |
| Connector Type | 3.5mm Jack (AUX-in), USB |
| Special Features | Touchscreen, Apple CarPlay, Android Auto, Bluetooth Hands-free, FM Radio, USB/TF Card Playback, AUX-in, Subwoofer Output, Backup Camera Support, 7-color Back-lights, Steering Wheel Control. |
9. Warranty and Support
For warranty information, please refer to the documentation included with your purchase or contact Mantian customer support directly. For additional support, you may refer to the official PDF user manual available online.
Official User Manual (PDF): Download PDF




