YIQIXIN CF920 Universal LCD Display Remote Car Key Instruction Manual

1. Introduction

This manual provides comprehensive instructions for the YIQIXIN CF920 Universal LCD Display Remote Car Key. This innovative smart key features an LCD touch screen and integrates advanced functionalities such as comfort access and, in some versions, Apple Find My compatibility. It is designed for a wide range of vehicles, including Mercedes-Benz W205, W203, W204, BMW E60, E61, E90, E70, E71, E87, Z4, E91, E92, E82, E88, and other models equipped with a one-button start system. Please read this manual thoroughly before installation and use to ensure proper operation and safety.

2. Safety Information

• Charging Precautions: Always use a standard charging head with the provided Type-C cable. Avoid using fast-charging heads, as this may damage the battery and shorten its lifespan.
• Compatibility: This smart LCD car key is compatible with vehicles that have an engine start/stop button. It is NOT suitable for vehicles that require a manual direct plug-in key or have a keyhole for starting the engine, even if the car can be started without physically inserting the key.
• Older Car Models: For some older car models, two keys may be required for operation. One key's circuit board is welded into the LCD key, and the other original key may need to be kept inside the car (e.g., in the key slot) for the engine to start. If your car requires this, ensure you follow this procedure.

3. Product Overview

3.1. Package Contents

The package typically includes:

• YIQIXIN CF920 LCD Smart Key (Silver or Black)
• OBD Module (for CF920FM version with locator)
• Wiring Harness
• USB Type-C Charging Cable
• User Manual

Image: Contents of the YIQIXIN CF920 Smart Key package.

3.2. Key Features

• Display: IPS TFT display with OGS touch screen for extended viewing.
• Material: High-quality alloy material (Zinc alloy) for durability and drop resistance.
• Functions: Supports original car key functions: Lock, Unlock, Trunk release, and a Multifunction button.
• Comfort Access (PKE): Automatic unlocking when approaching the vehicle (within 1-1.5 meters) and automatic locking when leaving the vehicle (beyond 3-5 meters). This feature requires the OBD module to be installed.
• Auto Window Function: When leaving the car (approx. 2-4 meters), the car will automatically lock, and the windows and sunroof (if supported by the car) will automatically close.
• Long Standby Time: Up to 30 days with the display active, and up to 365 days using only physical buttons (without comfort access).
• Optional "Find My" Function (CF920FM version): Utilizes the Apple Find My App for car location tracking.
• Anti-loss Feature: Allows input of owner information for recovery.

3.3. Physical Layout

Image: Smart Car Key design features, indicating Power button, Lock, Unlock, Trunk buttons, and USB Portal.

3.4. Dimensions

• LCD Key: Approximately 8.6cm (Height) x 4.8cm (Width) x 2.8cm (Depth).
• Compatible PCB Size: Max 3.8cm (Length) x 5.0cm (Width) x 0.5cm (Depth).

Image: Smart Car Key dimensions.

Image: Circuit board size compatibility diagram.

4. Specifications

5. Setup and Installation

5.1. Compatibility Check

The YIQIXIN CF920 Smart Key is designed for vehicles equipped with a one-button start/stop engine function. It is not compatible with vehicles that use a traditional key ignition or require a key to be inserted into a slot to start the engine.

Image: Visual guide for compatible (push-button start) and incompatible (key ignition) systems.

5.2. Required Tools

• Soldering iron
• Small screwdriver set
• Wire cutters/strippers

5.3. Installation Steps (Key Assembly)

This process involves transferring the circuit board from your original car key into the new LCD key shell and wiring it. If you are not comfortable with soldering, it is recommended to seek assistance from a professional locksmith or mobile phone repair shop.

Image: Installation Tutorial - Steps 1 & 2.

1. Prepare Original Key: Obtain your original remote car key.
2. Extract PCB: Carefully open your original remote key and remove its circuit board (PCB).
3. Prepare Wiring Harness: Take the provided wiring harness.
4. Solder Power Wires: Solder the red wire of the harness to the positive (+) terminal and the black wire to the negative (-) terminal on the battery position of your original key's circuit board.
5. Solder Function Wires: Solder the remaining wires (Lock, Unlock, Trunk, Multifunction) from the harness to their corresponding button points on the original key's PCB. Refer to the rubber ring colors for guidance. If your original key has four buttons, solder the yellow wire for the multifunction button.
6. Insert PCB into LCD Key: Plug the wired harness, with your original PCB attached, into the IC socket inside the LCD key. Ensure it is inserted in the correct direction.
7. Pad and Close: Place the sponge padding under the soldered circuit board for protection. Close the LCD key shell and secure it with screws.
8. Signal Check: Ensure the original circuit board chip faces outwards and is not obstructed, as this could interfere with signal reception and comfort access functionality.

Image: Detailed wiring diagram for connecting the original key's PCB to the LCD key's harness.

Image: Installation Tutorial - Steps 3 & 4, showing PCB insertion and OBD connection.

5.4. OBD Module Installation (for Comfort Access and Find My)

For the Comfort Access and Apple Find My features (CF920FM version) to function, the OBD module must be installed:

1. Connect the antenna wire to the OBD module.
2. Locate your vehicle's OBD port, typically found under the steering wheel.
3. Insert the OBD module firmly into the OBD port.

5.5. Non-Destructive Installation

The design allows for a non-destructive installation. If you wish to revert to your original key, you can carefully remove the wires and the original PCB from the LCD key shell and reassemble your original key. The wiring harness can also be removed from the LCD key if not needed.

6. Operating Instructions

6.1. Basic Key Functions

The LCD smart key replicates the functions of your original car key:

• Lock: Tap the lock icon on the LCD screen or press the physical lock button to lock your vehicle.
• Unlock: Tap the unlock icon on the LCD screen or press the physical unlock button to unlock your vehicle.
• Trunk Release: Tap the trunk icon on the LCD screen or press the physical trunk button to open your vehicle's trunk.
• Multifunction: Use the designated multifunction button for any additional features your original key supported.

6.2. Comfort Access (PKE)

With the OBD module installed, the key provides a seamless comfort access experience:

• Automatic Unlock: As you approach your vehicle (within 1-1.5 meters), the car will automatically unlock.
• Automatic Lock: As you walk away from your vehicle (beyond 3-5 meters), the car will automatically lock.

Image: Car factory standard comfort access function.

6.3. Auto Window Keyless Entry Function

This feature, supported by some car models, enhances convenience:

• When leaving the car (approximately 2-4 meters), the vehicle will automatically lock, and the windows will auto-close. If your car has a sunroof, it may also close automatically.

Image: Auto window keyless entry function.

6.4. "Find My" Function (CF920FM Version Only)

For the CF920FM version, you can locate your car using Apple's Find My network:

• Requirements: An iPhone running iOS 14.5 or higher.
• Usage: Open the Apple Find My App on your iPhone to view your car's last known location.
• Location Accuracy: The location is determined by a network of billions of iOS users worldwide. Note that real-time, continuous tracking may depend on nearby Apple devices. This functions similarly to an AirTag.
• No SIM/Data: This feature does not require a SIM card or mobile data traffic.
• No Audio Recording: The device does not support audio recording.

Image: Apple official Find My App integration for car location.

6.5. Charging the LCD Key

To charge your LCD key:

• Connect the provided Type-C charging cable to the USB port on the key.
• Plug the other end into a standard USB charging adapter (not a fast charger).
• A full charge provides approximately 30 days of standby time with the display active. Physical buttons can function for up to 365 days without comfort access, even if the display battery is depleted.

Image: Ultra long standby feature of the smart key.

7. Maintenance

• Cleaning: Wipe the LCD screen and the key body with a soft, dry, lint-free cloth. Avoid using abrasive cleaners, solvents, or harsh chemicals, as these can damage the screen or finish.
• Battery Care: To prolong battery life, avoid completely draining the battery frequently or leaving it uncharged for extended periods. Charge the device regularly using only a standard charger.
• Storage: Store the key in a dry place, away from direct sunlight, extreme temperatures, and high humidity.
• Impact Protection: While made with alloy material for durability, avoid dropping the key or subjecting it to strong impacts to prevent damage to the screen or internal components.

8. Troubleshooting

• Key Not Responding:
  • Check the battery level of the LCD key. Recharge if necessary.
  • Ensure the original car key PCB is correctly installed and all wires are securely soldered inside the LCD key.
  • Verify that the circuit board chip is facing outwards to prevent signal blocking.
• Comfort Access Not Working:
  • Confirm the OBD module is correctly installed in your vehicle's OBD port and is receiving power.
  • Ensure your car model supports the comfort access feature with this LCD key.
  • Check for any potential signal interference in the vicinity.
• Auto Window Function Not Working:
  • Verify that your specific car model supports this automatic window closing feature with the LCD key.
  • Ensure the comfort access function is operational, as these features are often linked.
• "Find My" Function Issues (CF920FM):
  • Confirm your iPhone is updated to iOS 14.5 or a newer version.
  • Understand that location updates rely on the presence of other Apple devices in the vicinity. If your car is in a remote area, updates may be less frequent.
• Engine Not Starting with LCD Key:
  • For some older car models, you might need to keep a second original key (or the original key's transponder chip) in the car, possibly in the ignition slot, for the engine to start. This is a known requirement for certain vehicles.

8.1. User Tips

• If you have soldering tools and experience, the welding step can be completed in approximately 5 minutes by following the instructions carefully.
• If you lack soldering tools or experience, it is advisable to visit a local mobile phone repair shop or locksmith for professional assistance with the welding and installation.
• Even if the LCD screen's battery is depleted, the physical lock and unlock buttons will continue to function for up to 6 months.
• The installation process involves carefully transferring your original car key's chip and soldering a special harness, then inserting it into the LCD key for use.

9. Warranty and Support

For any warranty claims, technical support, or further assistance, please contact the seller or manufacturer directly. Ensure you retain your proof of purchase for warranty validation.