For E36 BMW owners, especially those diving into engine swaps or troubleshooting immobilizer issues, the Electronic Immobilizer System (EWS) can be a source of much confusion. Online forums are rife with misleading information, often generalizing across different EWS versions and OBD systems. This article aims to clarify the complexities surrounding “EWS delete,” specifically for OBD2 E36 models, and provide accurate, expert-level insights for the English-speaking BMW community. We’re here to set the record straight and guide you through the nuances of EWS in your E36.
The primary purpose here is to debunk the oversimplified “EWS delete” solutions circulating online. You might encounter threads suggesting a simple wire snip will bypass the EWS on your E36. While such methods might have worked on very early “Drive Away Protection” systems, they absolutely will not be effective on later EWS 2 systems found in OBD2 E36s. Attempting these outdated bypasses on OBD2 models can lead to unnecessary headaches and further complications.
This guide is also for enthusiasts considering engine upgrades, like swapping an OBD2 engine (M52, S52) into an earlier E36 chassis that originally lacked EWS, such as a ’93 325i. Understanding the intricacies of EWS 2 in OBD2 systems is crucial for a successful swap.
Before we delve deeper, it’s highly recommended to review this genuine BMW service document for a foundational understanding of EWS:
http://www.europeantransmissions.com/Bulletin/DTC.BMW/understandthe%20EWS%20BMW.pdf
This document outlines the evolution of anti-theft systems in E36s, detailing the different versions and their implementation across production years and models. Notably, EWS 2 was implemented in all E36s produced from January 1995 until the end of production.
Understanding EWS 2 and OBD Differences
The real confusion arises with EWS 2 because it was used with both OBD1 and OBD2 Digital Motor Electronics (DME) or Engine Control Units (ECU). The linked PDF, while informative, doesn’t explicitly address the differences between OBD1 and OBD2 DME systems in conjunction with EWS 2. It’s critical to understand that solutions applicable to an OBD1 Bosch 413 DME are not necessarily transferable to the Siemens MS41.1 DME used in OBD2 cars. The latter cannot be chipped in the traditional sense but requires flashing or programming with specialized tools.
Let’s clarify the DME situation:
- Bosch 413 DME (Red Label): Generally considered non-EWS.
- Bosch 413 DME (Silver Label): An EWS DME, but the exact EWS version can be ambiguous. It’s crucial to determine if it’s designed for EWS 1 or EWS 2, or if there were indeed two distinct silver label 413 variants for each EWS version. Some information suggests red label 413s were used with EWS 1, while silver labels were associated with EWS 2. Further verification is beneficial.
- Siemens MS41.1 DME: Used in OBD2 E36s, and definitively EWS 2. This DME cannot be bypassed as easily as some 413 DMEs.
For the silver label 413 DME, often associated with EWS bypasses, you might find “EWS delete chips.” Turner Motorsport, for example, offers a chip for 413 DMEs designed to bypass EWS, while also incorporating performance enhancements.
http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=413%20D-EWS
Crucially, these chip-based bypass solutions are NOT applicable to OBD2 cars utilizing the Siemens MS41.1 DME. This is where much misinformation leads to frustration.
OBD2 EWS Delete Solutions for Engine Swaps and Beyond
Now, focusing on OBD2 engine swaps into older E36s without factory-installed EWS, or for those needing to disable EWS on an OBD2 E36, you have a couple of primary paths:
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DME Flashing/Reprogramming: The most common and reliable method for “E36 Obd2 Ews Delete” involves sending your Siemens MS41.1 DME to a specialist for reprogramming. This process essentially flashes the DME software to ignore the EWS 2 signal, effectively deleting the immobilizer function. This requires professional services and sending your DME away for reprogramming. Research reputable BMW tuning or DME service providers who offer EWS delete services for MS41.1 DMEs.
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Utilizing the Donor Car’s EWS System (Workaround): If your donor engine (M52 or S52 OBD2) comes with its complete EWS 2 system, including the EWS module, antenna ring, and chipped key, you can potentially integrate this into your older E36. This is a more unconventional approach but can bypass the need for DME flashing.
- You would need to install the antenna ring from the donor car around your ignition barrel.
- The chipped key from the donor car needs to be positioned near the antenna ring for the EWS system to recognize it. Some simply tape the key near the ring, concealed under the dash.
- This method retains the EWS functionality but essentially circumvents the need for key recognition via the ignition lock, as the donor key is permanently present and recognized.
While option 2 is a workaround and not as clean as a DME flash, it can be a viable solution to get an OBD2 engine running in an older E36 chassis without the expense and downtime of sending out the DME.
For a visual representation of a similar workaround concept (though not E36 specific), this link provides some insight:
http://www.drdetailshop.com/doc1060.htm
Wiring Diagrams and Further Resources
For anyone working with E36 electrical systems, especially when dealing with EWS or engine swaps, wiring diagrams are invaluable. This resource offers a comprehensive collection of BMW schematics:
http://wedophones.com/BMWManualsLead.htm
This wealth of information should help clarify the often-misunderstood EWS systems in E36 BMWs and, specifically, the “e36 obd2 ews delete” process. Remember, accuracy is paramount when dealing with these systems. Avoid conjecture and always verify information with reliable sources, like the BMW service document linked earlier.
If you have definitive answers to the DME questions raised, or additional accurate information regarding EWS systems, please contribute to the discussion. Let’s keep the information accurate and helpful for the BMW community.
