BMWeb

Find out what's wrong with your BMW, right in your browser.

Plug a cheap diagnostic cable into your car, open BMWeb, and see what the dealer's computer sees: fault codes in plain English, live engine data, and component tests. Free, nothing to install.

Open BMWeb Works with 1996 to 2006 BMWs (E36, E39, E46, E53 and more)
BMWeb's vehicle picker: a grid of BMW chassis from E31 to R50.
An E46's control modules listed by system: engine, transmission, chassis, body and more.
The Apps hub: fault lookup, wiring diagrams, parts catalogue, Tool32 and tuning.
ECU Backup: reading an MS45.1 DME's full flash off the car to a .bin file, with a live progress log.
A repair document for an E46 General Module: connector locations and the pin assignments at plug X253, opened in a tab.
The tuning editor: an 8 by 8 torque scaling map from an MS45 firmware image, heat-coloured, with interpolate and smooth tools.
Sharing your car remotely: BMWeb shows a short code to give the person connecting.
The helper's view: connected to the shared car, waiting for the owner to let them in.
The owner is asked to admit or reject someone requesting to connect to their car.
Before any write, the owner approves the exact action the helper wants to run.
A live remote session: a red REMOTE badge and an orange frame while the helper drives the car.
A look inside BMWeb. Click a screen to enlarge it, or see every screen.

What you need

A K+DCAN cable (about $20) The common USB diagnostic cable for these BMWs, sold everywhere online.
A 1996 to 2006 BMW 3 Series, 5 Series, 7 Series, X3, X5, Z4 and more. The cable plugs into the round port under the hood or the OBD port by your knee.
Chrome or Edge on a computer That's it. No Windows, no INPA install, no virtual machine.

Three steps

Plug in the cable. One end in the car, the other in your computer. Turn the ignition on.
Open BMWeb and pick your car. Click the orange button above, choose your model, and allow the cable when the browser asks.
Read your car. Scan every module for faults, watch live data, or test components. The same screens BMW technicians used.

Common questions

Is it safe to poke around?
Reading is completely safe, you're only listening. Anything that changes the car asks you first.
Does it cost anything?
No. BMWeb is free and open source. Your only cost is the cable.
Will it work on my phone?
For everything that does not touch the car. Download the offline zip and open it in Microsoft Edge (iPhone and Android are both supported) for fault lookup, wiring diagrams, documents and parts. Talking to the car needs the K+DCAN cable and a desktop browser with Web Serial, which phones do not have.
Do I need internet at the car?
Only the first time. Once BMWeb has loaded, it works offline, and there are offline downloads too.