3 Ways to Disassemble VW MQB49 5D Smart Key

XHORSE and KEYDIY now both support adding keys by reading the original MQB49 5C 5D key data. Some customers have asked us how to disassemble the VW Golf 8 style 5D smart key. We introduce three methods for reference. Hope it helps.

NOTE: For 5D system, only use original key to add a spare key.

 

Method 1
Step 1: Remove the mechanical key
There is a small button on the side of the key. Press it to release the mechanical key.
Press the button once to eject the mechanical key.
Press it again to pull the key out completely.

Step 2: Disassemble the outer casing
Insert the mechanical key into the slot and push upward to open the battery cover.
Remove the 2032 battery.

Insert a screwdriver into this side.
Insert another screwdriver into the opposite side and pry open the casing.
This will allow you to remove the black silicone cover.

Insert a flat-head screwdriver and push downward to release both metal edges.
The corner of the key remains undamaged.
The metal edges also remain intact.

Step 3: Remove the circuit board
Use a screwdriver to pry open the circuit board.
It is not necessary to completely remove the board.
Pry it open to this position, then gently push the circuit board with the screwdriver to lift it out.

Method 2

Use a pry tool to remove the side of the remote with the Volkswagen logo.

Take out the mechanical key.

Use a pry tool to detach the two metal edges.

Twist the metal edges up and down to disengage them from the pins here.

Use diagonal cutters to create a notch at the corner of the waterproof inner shell.

Then use a pry tool to forcefully separate the inner shell.

Finally, remove the key circuit board.

Method 3
Remove the mechanical key.
Take off the logo side of the key shell.

Gently lift the battery upward with a screwdriver to remove it.

Use a screwdriver to pry off the metal edges.

Remove the black rubber covering.

Insert a screwdriver into this part, then lift upward without applying excessive force.

This will release the metal edge.

Remove the remaining small components.

Use a pry tool to forcefully separate the inner shell.
Finally, take out the key circuit board.

Read also:

How to Distinguish an Audi Key is 5C or 5D from Key Shell?

Difference Between AutoTuner and bFlash

Two standout options in ECU programming are Autotuner and bFlash, both designed for reading and writing ECUs and TCUs (Transmission Control Units) via methods like OBD, bench, and boot. While they share core functionalities, they cater to slightly different user needs, with Autotuner emphasizing simplicity and cost-effectiveness, and bFlash focusing on advanced diagnostics and future-proofing.

This article dives into their differences, drawing from user reviews, forum discussions, and expert comparisons to help you decide which tool might suit your workshop or tuning business.

Overview of Autotuner

 

Autotuner is a universal ECU/TCU remapping tool praised for its straightforward design and broad compatibility, particularly with modern European vehicles like those from BMW, Volkswagen Group (VAG), and Mercedes.

It supports OBD and bench tuning in a single device, with features like live data logging and quick protocol updates. One of its biggest selling points is the lack of subscription fees—users get lifetime free updates and a 5-year warranty, making it a budget-friendly choice for long-term use.

 

Reviews on platforms highlight its ease of use, with users calling it “extremely easy” for tasks like ECU unlocks and praising the intuitive interface that allows mastery in seconds.

YouTube reviews emphasize its speed and reliability for newer German cars, with one tuner noting it’s “the best tuning tool” for beginners due to no annual costs and strong logging capabilities.

Overview of bFlash

bFlash positions itself as an all-in-one solution for ECU programming, diagnostics, and real-time tuning, developed by tuners for tuners.

It excels in multi-method programming (including OBD, BDM, Boot, DoIP Ethernet, FlexRay, and JTAG) and includes advanced tools like CAN bus analysis, ECU emulation (via bTrace), and high-speed data logging.

Designed for future-proofing up to 2030 ECUs, it’s particularly strong for complex diagnostics and modern vehicles.

User reviews on Trustpilot give it a 4.5/5 rating, with praise for its reliability, speed, and “excellent after-sales response.”

Forum users and YouTube demonstrations highlight its bespoke features, like real-time tuning and built-in log viewers, with one reviewer calling it a “tuner’s tool” that’s “solid and dependable” for daily use.

On the downside, some note bugs in logging, limited support for older ECUs, and the subscription model (typically annual) that can add to long-term costs.

It’s also more expensive upfront compared to some rivals.

Key Differences: A Side-by-Side Comparison
Here’s a breakdown of how Autotuner and bFlash stack up. This table focuses on aspects frequently mentioned in user feedback, such as usability, features, and value.

 

Aspect	Autotuner	bFlash
Primary Focus	Simple, fast read/write operations with emphasis on ease for Mercedes and VAG vehicles.	Advanced diagnostics, real-time tuning, and multi-protocol support for future ECUs.
Pricing Model	No subscription; one-time purchase with free lifetime updates.	Subscription-based (annual fees apply); higher initial cost but includes advanced features.
Usability	Highly intuitive interface; “best for starters” per Reddit users, with quick setup.	User-friendly but more complex due to advanced options; praised for clear software resembling Autotuner.
Vehicle Coverage	Strong on modern European cars (e.g., EDC16 to MD1); broad but not the widest.	Targeted at high-end and newer vehicles; supports over 6000 types but lacks some older OBD protocols.
Advanced Features	Live data logging; accessories for anti-tuning systems.	Diagnostics, CAN bus recording, ECU emulation; “packed with powerful features” per official site.
Pros from Reviews	Affordable long-term, reliable for daily tuning, excellent warranty; “fast and stable” (Trustpilot 4.9/5).	Superior support, future-proof; “the best on the market” for diagnostics (Trustpilot 4.5/5).
Cons from Reviews	Software environment not the most polished; support can be hit-or-miss.	Bugs in logging, expensive subscriptions; less OBD support than rivals.

In-Depth Analysis from User Reviews

 

Usability and Learning Curve
Autotuner shines in reviews for its plug-and-play simplicity. A YouTube guide describes it as “interactive and simple,” ideal for those new to tuning, with no need for constant updates or fees.

Forum users on Facebook echo this, calling it the “best user interface” without subscriptions.

In contrast, bFlash’s advanced features can overwhelm beginners, but experienced tuners appreciate the depth. It’s “very good” but requires more engineering knowledge, with logging issues deterring some.

 

Support and Reliability
Both tools receive high marks for support, but bFlash edges out with “super-fast” responses and “excellent service” in reviews.

Autotuner’s community and free resources are solid, but some users criticize slower help compared to premium tools.

Reliability is a tie:
Autotuner is lauded for stability in European vehicles, while bFlash is “dependable” for modern ECUs but criticized for occasional bugs.

Value for Money

Autotuner’s no-subscription model is a frequent highlight, making it “one of the best value-for-money tools”.

bFlash’s subscriptions are a common complaint, but users justify the cost for its exclusive features like Mercedes ECU unlocks.

 

Vehicle and Feature Coverage

Reviews often compare coverage: Autotuner is “superior” for quick Mercedes protocols, per forums.

bFlash stands out for diagnostics and emulation, with users saying it’s “more up-to-date from an engineering point of view.”

For VAG-focused tuners, opinions split—some prefer Autotuner for its speed, others bFlash for depth.

 

Conclusion:

Which One Should You Choose?

Ultimately, the choice between Autotuner and bFlash depends on your needs. If you’re a beginner or focused on cost-effective, straightforward tuning for European vehicles, Autotuner is the crowd favorite—its no-fee model and ease of use make it ideal for growing workshops.

For advanced users needing diagnostics, real-time tools, and future-proofing, bFlash’s feature set justifies the investment, as evidenced by its strong tuner endorsements.

Both are highly rated (Autotuner at 4.9/5, bFlash at 4.5/5 on Trustpilot), so consider your budget and vehicle focus before deciding. Whichever you pick, these tools represent the pinnacle of ECU programming in 2026.

 

Modify Keydiy KD-MAX Renew Cable to Read VAG 5C 5D Key Data

Keydiy KD-MAX now will also read VAG MQB49 5C 5D original key data. Update KD-MAX to 2.3.0 and newer.

KD-MAX does not have a dedicated cable to read 5C/5D keys.

We can modify the remote renew cable that came in the package to read 5C 5D keys.

There are 2 remote renew cables in the KD-MAX package.

Modify one of the renew cables like this

Then solder the modified cable to the key PCB as key wiring diagrams shown in the KD-MAX device.

NOTE: Need to learn key with KD-MATE after reading key data.

Keydiy KD-MP MLB Key ID is FFFF Solution

Problem:

It’s a 2021 model year Porsche Taycan EV Turbo S. Tried to read original key data and add a spare KD MLB19 OEM-solution key with Keydiy KD-MP MLB tool.

The software said the key ID is FFFFFFFF. Any solution?

 

 

Solution:

If the brand new KD blank MLB key shows ID all FF, it cannot be used to generate dealer key directly.

You need to modify key ID, then generate dealer key.

Select “Modify key ID” function to modify key ID and try again.