On-The-Fly Controls
Change supported feature states and values without performing a full reflash.
MG Flasher Feature SystemCustom Code
Custom Code
for BMW DME Control
Extend, replace and improve selected OEM DME functions with MG Flasher Custom Code. Access supported On-The-Fly controls, app-based settings, diagnostics, protection logic and advanced calibration features on compatible vehicles.
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Custom Code System
Control. Configure. Diagnose.
ECU Dependent
App Control
Use Live Control and Custom Code Diagnostics on compatible software versions.
Custom Logic
Enable functionality that extends or improves selected OEM DME behaviour.
Diagnostics & Protection
Read supported states, DTCs and protection information directly in MG Flasher.
Important:
Available features depend on the vehicle, ECU software, installed Custom Code version,
calibration and selected options.
Overview
Software Beyond the Factory DME.
MG Flasher Custom Code adds supported functionality directly to the vehicle’s Digital Motor Electronics. It can extend existing OEM behaviour, introduce new controls and provide additional ways to interact with the calibration from the vehicle or the MG Flasher app.
Not every feature is available for every ECU software version. The exact feature set depends on the installed Custom Code release, engine platform, generation, software level and calibration.
What Custom Code Is
A software feature layer inside the DME
Custom Code works with supported calibrations to provide advanced controls and additional ECU logic.
Not a separate piggyback moduleFunctionality is integrated into supported DME software.
Not identical on every vehicleSupport depends on ECU software and the available Custom Code version.
Feature SystemCCM Features and
CCM Features and
Additional Custom Code.
Seven features occupy the 1K–7K Custom Code Menu positions. Additional Custom Code functions are controlled through the app, diagnostics, calibration logic or supported hardware integrations without their own CCM tachometer position.
Custom Code Menu
CCM positions 1K–7K
These RPM values are temporary menu positions, not engine-speed activation thresholds.
1KMaps
Switchable Maps
Select a valid map slot without performing a full reflash.
Explore → 2KExhaustBurbles On-The-Fly
Select supported burble profiles, the app slider or Burble OFF.
Explore → 3KCoolingMax Cooling
Enable or disable the supported enhanced cooling strategy in real time.
Explore → 4KPerformanceAnti-Lag
Open the Anti-Lag submenu and configure supported launch-control behaviour.
Explore → 5KFuel InputEthanol Content
Use 5K for Ethanol Override. Ethanol Content Display is a related, separate tachometer function.
Explore → 6KExhaustExhaust Flap
Select OEM, Closed or Open on compatible vehicles with an electronic exhaust flap.
Explore → 7KControlled AccessValet Mode
Enable or disable the configured vehicle-speed, engine-speed and torque restrictions.
Explore →
Additional Custom Code Features
App, calibration and integration functions
These functions do not occupy additional positions after 7K in the Custom Code Menu.
FFCalibration
Flex Fuel Blending
Interpolate supported PF, FF1 and FF2 calibration data using an ECA or manual ethanol value.
Explore → APPCoolingRadiator Flap
Select OEM, Closed or Open through compatible Live Control or Custom Code Diagnostics. No CCM position.
Explore → CANIntegrationMotiv ReFlex
Connect supported port-injection, ethanol and low-pressure fuel data to the DME.
Explore → OEMOEM FunctionRemote Starter
Restore compatible factory Remote Starter functionality on selected Gen 2 vehicles.
Explore →
Control Methods
Three Ways to Interact with Custom Code.
The exact methods available depend on the installed Custom Code version and the supported vehicle setup.
01
MG Flasher AppLive Control
Adjust supported feature states and values directly while connected to the vehicle.
- Real-time DME values
- Feature-level and slot-level availability
- Compatible with selected Custom Code v6.9+ functions
02
Vehicle ControlsCustom Code Menu
Use supported steering-wheel inputs, the tachometer and CEL as a temporary feature menu.
- UniRocker or RockerCombo
- Feature submenus from 1K to 7K
- Counted CEL blinks confirm submenu selection
03
TroubleshootingCustom Code Diagnostics
Read supported EEPROM states and set selected values through the MG Flasher diagnostic page.
- Read active feature values
- Set supported feature values
- Save EEPROM through an ignition cycle
Version Evolution
Custom Code Changes with Each Release.
The installed version determines which feature controls, diagnostics and integrations are available.
Foundation Support
Used on supported platforms where newer v7 releases are not available and includes selected foundational features.
Diagnostics & Live Access
Custom Code Diagnostics and selected Live Control functions become available on compatible setups.
Cloud Releases & EEPROM
Custom Code moves to cloud-based releases and On-The-Fly states gain long-term EEPROM storage.
CCM & Expanded Controls
Custom Code Menu and compatible Ethanol Override, Exhaust Flap, Radiator Flap and Valet Mode controls become available.
ReFlex, DTCs & Protection
Motiv ReFlex integration, supported Custom Code DTC logging and compatible protection strategies become available.
Flex Fuel Blending
Compatible PF, FF1 and FF2 calibration blending and newer ethanol-based Custom Code logic are added.
EEPROM Storage
Your On-The-Fly Settings Can Persist.
From Custom Code v7.0, supported On-The-Fly settings can be stored in ECU EEPROM. This helps preserve selected feature states between flashes, battery changes and maintenance work.
The documented saving procedure requires an ignition cycle. Custom Code v7.0.1 resolved the original v7.0 issue that prevented the saving process from being triggered correctly.
Examples of Persisted Settings
01Switchable Map slot
02Burble aggression level
03Max Cooling status
04Stationary Anti-Lag RPM
05Newer supported OTF settings
Diagnostics
Read States. Set Values. Investigate Faults.
Custom Code Diagnostics exposes supported controls according to the version installed on the connected ECU.
Read All EEPROM
Check active values and states for available On-The-Fly options.
Set Supported Values
Adjust selected map slots, states and feature values from the app.
Save EEPROM
Initiate the documented ignition-cycle saving process.
Read DTCs
Open Diagnostics → Read DTC to review supported Custom Code fault codes and protection events.
Diagnostics availability begins with compatible Custom Code v6.9+. Selected Anti-Lag diagnostics require v7.0+.
Ethanol Override, Exhaust Flap, Radiator Flap and Valet Mode controls require compatible v7.1+ configurations,
while supported Custom Code DTC logging is available on compatible v7.2+ setups.
Compatibility
Check the ECU Software, Not Only the Vehicle Model.
Two visually similar vehicles can support different Custom Code versions because their ECU software is different.
Connect with MG Flasher
Use a compatible ENET connection and open the vehicle in the app.
Read ECU Info
Open Diagnostics and use Read ECU Info to identify the active SWFL/software version.
Check Available Custom Code
Confirm which Custom Code release is supported for the exact ECU software.
Confirm Feature Support
Review whether the desired function is included in that version and calibration.
Current Public Guidance
Use v7 where supported
Documentation identifies Custom Code v3, v4, v5 and v6 as deprecated.
Custom Code v7.xPreferred where available for the ECU software.
Custom Code v0.5Used on supported software where v7 is unavailable.
Download MG Flasher
Cloud-Based Releases
Custom Code Updates Are Independent from App Releases.
From v7.0, MG Flasher moved Custom Code releases to cloud services. This allows Custom Code updates and release notes to be delivered separately from normal MG Flasher app updates.
01Separate release cycle
02Dedicated Custom Code release notes
03ECU-specific availability still applies
FAQ
MG Flasher Custom Code FAQ.
Common questions about compatibility, versions, controls, diagnostics and On-The-Fly settings.
What is MG Flasher Custom Code?
Custom Code is a software feature layer for compatible DMEs that can extend, replace or improve selected OEM ECU functions.
Is every Custom Code feature available on every vehicle?
No. Availability depends on the engine, vehicle generation, ECU software, installed Custom Code version, calibration and selected options.
How can I control Custom Code features?
Depending on compatibility, users can use Live Control, Custom Code Menu steering-wheel controls or Custom Code Diagnostics.
What is the Custom Code Menu?
CCM temporarily uses supported steering-wheel inputs, the tachometer and the Check Engine Light to navigate and confirm On-The-Fly feature selections.
Do Custom Code settings remain after restarting the vehicle?
Supported On-The-Fly settings can be stored in EEPROM on compatible Custom Code v7.0+ releases after the documented ignition-cycle saving process.
Which Custom Code version should I use?
Use the newest compatible version available for the exact ECU software. Current documentation recommends v7 where supported and v0.5 where v7 is unavailable.
How do I check my ECU software?
Connect the vehicle, open Diagnostics in the MG Flasher app and use Read ECU Info to view the active SWFL/software version.
Does Custom Code update with the MG Flasher app?
From Custom Code v7.0, releases are cloud-based and can be updated independently from normal MG Flasher app releases.
Ready to Check Your Vehicle?
Find the Custom Code Available for Your ECU.
Download MG Flasher, connect the vehicle and confirm the exact software and feature support before flashing.