Unlocking a Bosch MD1 or MG1 control unit no longer requires sending it out. Using Magic Motorsport Flex boot glitch method, you can perform the initial unlock on your bench, after which you can read and write the ECU over bench mode without repeating the process.
Here is the exact procedure broken down using a locked Bosch MD1 CS003 ECU as an example.
- Opening the Housing
Start by removing the casing screws.
Carefully run a blade around the edge to cut through the silicone adhesive, then work around the perimeter with an ECU opening tool.
Take your time to prevent prying against board components.
Once inside, check the Flex wiring diagram to identify the resistor that needs to come off.
- Desoldering the Resistor
Dab a small amount of liquid flux on the target resistor.
Heat both solder joints using a fine soldering tip or hot air station, then carefully remove the component.
- Wiring Up
Connect Flex Box and Flex ECU tool
Plug Magic FLX4.1 Adapter into Flex Box
Use the combined boot and bench cable harness to connect FLEX BOX and locked Bosch MD1 CS003 ECU as shown in the Flex software wiring diagram (Manuals) for your specific ECU model.
- Running the Unlock Glitch
Hit Connect in the Flex software, then click Unlock.
Keep in mind:
- The glitch sequence can take up to 25 minutes.
- If it fails on the first pass, run the routine again. It frequently requires multiple attempts before successfully glitching the processor.
- Board Cleanup and Testing
Once Flex confirms a successful unlock, apply flux and solder the resistor back onto its original pads.
Double-check your solder connections with a multimeter to verify continuity.
The module is now unlocked and ready for standard bench reading and writing.
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