This guide demonstrates how to add a new key to BMW G-Series vehicles equipped with BDC2 modules using Launch X431 IMMO series tablets (IMMO Plus / IMMO Elite / IMMO PAD / IMMO Pro), X-Prog3, and MCU3 Adapter on bench mode. The example used here is a 2019 BMW G Series.
Requirements
- Update BMW/Mini software to version V10.40 or later version
- Need at least one original key
- Need network connection via USB (do not use Bluetooth)
Note: Adding a BDC2 key is a complex process. Please strictly follow the step-by-step guide below to ensure successful operation. Any deviation may result in failure or errors during programming.
Main Steps
Step 1: Read ECU Information
Step 2: Back Up Coding Data
Step 3: Pre-processing
Step 3: Generate Dealer Key
Operation guide:
Note: The software interface is shown in Chinese below, but you can still follow the general steps.
1. Initial Setup
- Go to the BMW/Mini IMMO software
- Connect the Launch X431 IMMO tablet to the vehicle using X431 X-Prog3
- Select Anti-theft key matching -> BDC02 IMMO System
Step-by-Step Key Programming
Step 1: Read ECU Information
- Read and confirm ECU information
- Detect the software version; if supported, continue with coding data backup
- If not supported, exit the operation
Step 2: Back Up Coding Data
- Select “Backup Coding” function
- Save the file name using only English letters and numbers
- Confirm coding data is successfully backup
Step 3: Pre-processing
- Disassemble the BDC2 module from the vehicle
- Select Programming Operation-> Pre-processing
- Ensure the following setup:
- At least one original key required
- Connect X-Prog3 Programmer, MCU3 adapter, and BC cable
- Use USB connection for stable data transfer (large file size)
- Launch X431 will display a connection diagram
- Connection Points:
- Connect the 8-foot chip 25LC256 pin 2
- Connect RESET PIN to the MCU
- Connect BC cable harness to ECU
- Keep idle harness away from ECU to avoid damage
- Connect an external 12V power supply to Launch X431 MCU3 Adapter (do not exceed 12V)
- In Case of Failure During Operation:
- Disconnect 12V power supply
- Disconnect MCU RESET and EEPROM PIN2 connections
- Reconnect 12V power to retry
- If SWFL version is lost, use Programming Restore to recover
- Back Up and Restore:
- Disconnect EEPROM PIN2 and the harness GND, pay attention to anti-static during operation, and only touch the insulated part.
- Back up CAFD coding data
- Connect EEPROM PIN2 and the harness GND, pay attention to anti-static during operation, and only touch the insulated part
- Disconnect EEPROM PIN2 and GND as instructed
Note: MUST follow every disconnect/connect PIN2 and GND operation.
- Read IMMO data, and update ECU
- Pre-processing completes
- Write original coding back to BDC2
- Confirm successful coding restore
Step 4: Generate Dealer Key
- Disconnect MCU Reset and X-Prog3 from B8
- You can either:
- Generate the key first, then reinstall the BDC2 module, or
- Reinstall BDC2 first, then generate the key
- After module installation:
- Check central control time display
- Ensure automatic mirror folding works; adjust manually if needed
- Key Generation:
- Go to Key Operation → Read Original Key Information
- Place working key in X-Prog3 to read info
- Select Generate Dealer Key
- Choose a key position
- Insert new key into Launch X431 X-Prog3 to program
- Confirm success and exit
Final Step: Key Testing
- Install BDC2 module
- Use emergency sensing area under steering wheel to activate the new key
- Start the vehicle
- Test remote control functionality
Done!
Learn more:
Launch X431 Update 2015-2021 BMW F/G Chassis IMMO Key Adding Function: