jlr-open-diag

English · Português

Open, cross-platform (Windows 11, macOS, Android) diagnostics and configuration tool for Jaguar Land Rover vehicles, reimplementing the functions of the JLR SDD (Symptom Driven Diagnostics) over the Mongoose Pro JLR adapter (J2534, USB).

First validated target: Land Rover Discovery 4 (L319) 3.0 SDV6 diesel. The architecture is generic across the SDD's whole coverage; other vehicles are added as they are validated.

Beta 0.1 — all four platforms (Windows, macOS, Android, web) build; reading and diagnostics were validated on a real car. Binaries under Releases. The Android connection is experimental (USB-OTG, not yet validated on a device) and CCF writing depends on a proprietary JLR binary — details below. The app UI is available in English, Spanish and Portuguese (language picker in the app bar; follows the system locale by default).

Current status

Reading and diagnostics work on the real car (validated on an L319 MY12). CCF writing is blocked by a proprietary JLR binary (the SBL) — see "Known blocker" below.

Area	Deliverable	Status
sdd-crypto	.exml codec (3DES)	✅
sdd-data / sdd-import	parsers → SQLite, .exml decrypt	✅
mongoose	native USB/serial protocol of the adapter	✅
diag	UDS/ISO-TP: VIN, module scan, DTCs with help, live data	✅ on car
ccf (read)	read + decode the BCM CCF	✅ on car
ccf (write)	edit and write the CCF	⛔ blocked (SBL)
Flutter app	UI (Windows/macOS/Android/web) + FFI/HTTP bridge	✅ builds on all 4; Windows/macOS/web connect; Android USB-OTG experimental
j2534-shim	capture SDD writing (unlocks the CCF)	🚧 planned
procedures	service routines (DPF, injectors, suspension…)	⬜
expansion	all vehicles covered by the SDD	⬜

Builds and install (beta 0.1)

Beta binaries under Releases. To build from source (load the environment with source env.sh first):

• Windows (native): bash app/jlr_app/build-windows.sh → jlr_sdd.exe (direct FFI to the Mongoose; requires VS Build Tools with the C++ workload).
• Android (APK): bash app/jlr_app/build-android.sh → app-release.apk (requires Android SDK/NDK + cargo-ndk; USB-OTG connection is experimental — see app/jlr_app/ANDROID.md). Also runs on Android Auto (read/clear faults, live charts; needs wireless Android Auto).
• macOS: bash app/jlr_app/build-macos.sh on a Mac → LR Scanner.app (see app/jlr_app/MACOS.md).
• Web + local server: run-app.bat (starts car-scan serve and opens the browser).

The app does not embed JLR data: generate your vehicle's pack from your own SDD install with sdd-import (it becomes app/jlr_app/assets/pack.json).

Known blocker: CCF writing (help wanted)

Reading and decoding the BCM's CCF (vehicle configuration) works. Writing does not: the BCM requires a Secondary Boot Loader (SBL) to be downloaded to its RAM before it accepts the erase/flash of the config region — without it, the erase replies 7F 31 22 (conditionsNotCorrect), even with the programming session and security correct. That SBL does not ship in a local SDD install: SDD fetches it from JLR's online server (TOPIx) at write time. The full investigation (DLL RE, on-car tests, decrypted data) is in docs/security-ccf-write.md.

Help wanted: writing the CCF on an L319 (EUCD) BCM needs JLR's Secondary Boot Loader (SBL), delivered from JLR online — it is not in a local SDD install. Everything else (reading/decoding the CCF, DTCs, live data, security access) works. If you have the L319 BCM SBL VBF, or a J2534 capture of SDD writing a CCF, please open an issue — that single piece is what's needed to finish offline CCF writing.

Data and rights principle

This repository does not contain Jaguar Land Rover data. The diagnostic databases (module definitions, DTCs, DIDs, CCF map, texts) belong to JLR and live in the user's own SDD install. The sdd-import tool reads that install locally, on the vehicle owner's machine, and generates data packs that are likewise not redistributed (see .gitignore).

Our own code is MIT-licensed. The mongoose crate, deriving from reverse engineering published under LGPL-2.1 (github.com/dgcarr/Mongoose-USB-2-OBDII-Linux-Driver), is LGPL-2.1. GPL code (e.g. 5555l/ccf_parser) is used only as a behavior reference, never copied.

Warning

Touching a vehicle's modules carries risk. Every write backs up first, requires ignition on with the engine off, and explicit confirmation. Use at your own risk.

Development environment

Toolchains live under C:\dev (portable, no admin needed): Rust (GNU toolchain + mingw-w64), Flutter, JDK, Ghidra; Android SDK/NDK under C:\dev\android. Load the environment with source env.sh before cargo/flutter.

source env.sh
cargo test            # tests all crates