Removing a speed limiter from a VW Crafter can be a tricky process, often requiring specialized tools and knowledge. This guide explores the use of VCDS (Vag-Com Diagnostic System) for this purpose, focusing on common issues and potential solutions. We’ll delve into a real-world scenario of a 2018 VW Transporter with a 70mph speed limit, highlighting the challenges and steps involved in attempting removal using VCDS.
Understanding VCDS and Speed Limiter Removal
VCDS is a powerful diagnostic tool that allows users to access and modify various control modules within a Volkswagen vehicle. It’s widely used for troubleshooting, customization, and coding changes. While theoretically capable of adjusting or removing speed limiters, success depends on several factors including the specific model year, engine code, and installed options. This isn’t always a straightforward process, and often requires a deep understanding of the vehicle’s software and coding structure. Incorrect modifications can lead to unexpected behavior or even damage to the vehicle’s systems.
Case Study: 2018 VW Transporter – “Controller Refused to Send a Seed”
A common issue encountered when attempting speed limiter removal with VCDS is the error message “Controller refused to send a seed, Error 7F service not supported in active session.” This error typically indicates that the control module is denying access to the necessary security functions required to make changes. The following autoscan data from a 2018 VW Transporter exemplifies this scenario:
[Autoscan data as provided in the original post]This log reveals the user attempted to access the engine module (Address 01: Engine) using security access code 27971. However, the controller rejected the code, preventing further modification. The autoscan also provides details about the vehicle, including:
- Engine Code: CXGB
- Part Number: 04L 906 056 KA
- Software Version: 4047
This information is crucial for identifying the correct procedures and potential solutions for speed limiter removal. Note that the autoscan didn’t reveal any fault codes in the engine module. However, faults were found in the Auto Dist. Reg (Address 13), which might be indirectly related to the speed limiter functionality and should be investigated further.
Potential Solutions and Considerations
Several factors might contribute to the “Controller refused to send a seed” error:
- Incorrect Security Access Code: Using the wrong code will always result in access denial. Finding the correct code for a specific vehicle and module can be challenging and might require access to online databases or specialized forums.
- Outdated VCDS Software: Older versions of VCDS may not support the security protocols implemented in newer vehicles. Updating to the latest version is crucial.
- Incompatible Interface: Using a non-genuine or outdated VCDS interface can lead to communication errors and access problems.
- ECU Coding Protection: Some ECUs have enhanced security measures that prevent unauthorized modification. Specialized tools or techniques might be required to bypass these protections.
Furthermore, determining the power output from the autoscan is not always straightforward. While the engine code (CXGB) provides some clues, a comprehensive vehicle database or decoder is usually necessary to get the exact power output figures.
Conclusion: Professional Assistance Recommended
Removing a speed limiter using VCDS is a complex process that requires technical expertise and the correct tools. While VCDS provides a powerful platform for vehicle diagnostics and modification, attempting to alter critical systems without sufficient knowledge can lead to undesirable outcomes. If you encounter difficulties or are unsure about any steps, consulting a qualified automotive technician specializing in VW vehicles is highly recommended. They possess the necessary expertise and equipment to safely and effectively address speed limiter removal. Attempting this modification yourself carries inherent risks and should be approached with caution.
